[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    167.162.64.0/19 [110/3] via 10.0.56.1, 00:04:46, GigabitEthernet0/0
O    172.154.202.0/24 [110/4] via 10.0.38.1, 00:03:26, GigabitEthernet0/1
O    216.91.0.0/17 [110/4] via 10.0.206.1, 00:02:52, GigabitEthernet0/0
O    172.154.201.0/24 [110/2] via 10.0.195.1, 00:02:45, GigabitEthernet0/1
O    160.100.180.128/25 [110/3] via 10.0.22.1, 00:05:10, GigabitEthernet0/0
O    172.154.203.0/24 [110/2] via 10.0.235.1, 00:04:19, GigabitEthernet0/1
O    172.154.204.0/24 [110/5] via 10.0.65.1, 00:04:16, GigabitEthernet0/1
O    172.154.205.0/24 [110/5] via 10.0.62.1, 00:02:59, GigabitEthernet0/1
O    172.154.200.0/24 [110/4] via 10.0.177.1, 00:04:31, GigabitEthernet0/1
C    192.168.147.0/24 is directly connected, GigabitEthernet0/0

Question: Identify all potential issues in this routing table and classify them by severity.

[Assistant]
<reasoning>
1. Observation: The routing table contains 6 contiguous /24 networks: 172.154.200.0/24, 172.154.201.0/24, 172.154.202.0/24... (and 3 more), all learned via OSPF through the same general area.
2. Analysis: These networks are sequential (172.154.200.0/24 through 172.154.205.0/24) and could be efficiently aggregated into a single summary route 172.154.200.0/21.
3. Impact: Missing summarization causes routing table bloat. Each /24 requires a separate entry, consuming memory and CPU. OSPF LSDB grows larger, increasing SPF calculation time. Route updates propagate individually, causing more frequent reconvergence.
4. Detection: 6 contiguous /24 prefixes with sequential third octets (200 to 205) indicate a missed summarization opportunity. All routes share similar metrics and next-hop patterns.
5. Recommendation: Configure route summarization on the ABR (Area Border Router) or originating router. Advertise 172.154.200.0/21 instead of individual /24 routes. This reduces routing table entries from 6 to 1 and improves convergence time.
</reasoning>
<answer>
WARNING: Under-summarization detected. 6 contiguous /24 networks (172.154.200.0/24 to 172.154.205.0/24) are advertised individually instead of being aggregated. Fix: Configure summary route 172.154.200.0/21 on the originating ABR to reduce routing table size from 6 entries to 1. This improves memory usage, CPU load, and convergence speed.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    172.67.200.0/22 [110/2] via 192.168.33.1, 00:03:16, GigabitEthernet0/0
O    198.237.137.24/30 [110/4] via 192.168.33.1, 00:01:45, GigabitEthernet0/0
O    57.108.0.0/17 [110/2] via 192.168.33.1, 00:04:23, GigabitEthernet0/0
C    192.168.128.0/24 is directly connected, GigabitEthernet0/0
O    16.129.118.128/29 [110/3] via 192.168.33.1, 00:03:30, GigabitEthernet0/0
S    172.201.0.0/22 [1/0] via 192.168.33.1
O    172.201.0.0/23 [110/3] via 10.0.226.1, 00:05:56, GigabitEthernet0/1
O    172.201.1.0/24 [110/2] via 172.16.96.1, 00:05:55, GigabitEthernet0/0

Question: Does this routing table have any routing inconsistencies?

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 172.201.0.0/22 (S, via 192.168.33.1) and 172.201.0.0/23 (O, via 10.0.226.1).
2. Observation: Additionally, 172.201.1.0/24 is learned via OSPF through 172.16.96.1, and this /24 is contained within both summaries.
3. Analysis: 172.201.0.0/23 is completely contained within 172.201.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.33.1 vs 10.0.226.1). For traffic to 172.201.0.0/23, the more specific /23 route wins, sending traffic to 10.0.226.1. For traffic to 172.201.2.0/24 and 172.201.3.0/24, the /22 route applies, sending traffic to 192.168.33.1. The specific route 172.201.1.0/24 overrides both, sending traffic to 172.16.96.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 172.201.0.0/23 ⊂ 172.201.0.0/22, but next-hops differ. The specific route 172.201.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 172.201.0.0/23 if 172.201.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 172.201.0.0/22 (S, via 192.168.33.1) and 172.201.0.0/23 (O, via 10.0.226.1) overlap but have different next-hops. 172.201.1.0/24 (via 172.16.96.1) further fragments forwarding. Fix: Remove redundant summary 172.201.0.0/23 and ensure all subnets within 172.201.0.0/22 use the same next-hop 192.168.33.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    3.146.32.0/19 [110/5] via 192.168.98.1, 00:02:25, GigabitEthernet0/0
O    172.158.1.0/24 [110/2] via 172.16.60.1, 00:03:51, GigabitEthernet0/0
C    192.168.189.0/24 is directly connected, GigabitEthernet0/0
O    51.57.0.0/16 [110/4] via 192.168.98.1, 00:01:22, GigabitEthernet0/0
S    172.158.0.0/23 [1/0] via 10.0.31.1
O    160.142.0.0/16 [110/4] via 192.168.98.1, 00:01:53, GigabitEthernet0/0
O    8.170.0.0/16 [110/5] via 192.168.98.1, 00:03:24, GigabitEthernet0/0
S    172.158.0.0/22 [1/0] via 192.168.98.1

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 172.158.0.0/22 (S, via 192.168.98.1) and 172.158.0.0/23 (S, via 10.0.31.1).
2. Observation: Additionally, 172.158.1.0/24 is learned via OSPF through 172.16.60.1, and this /24 is contained within both summaries.
3. Analysis: 172.158.0.0/23 is completely contained within 172.158.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.98.1 vs 10.0.31.1). For traffic to 172.158.0.0/23, the more specific /23 route wins, sending traffic to 10.0.31.1. For traffic to 172.158.2.0/24 and 172.158.3.0/24, the /22 route applies, sending traffic to 192.168.98.1. The specific route 172.158.1.0/24 overrides both, sending traffic to 172.16.60.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 172.158.0.0/23 ⊂ 172.158.0.0/22, but next-hops differ. The specific route 172.158.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 172.158.0.0/23 if 172.158.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 172.158.0.0/22 (S, via 192.168.98.1) and 172.158.0.0/23 (S, via 10.0.31.1) overlap but have different next-hops. 172.158.1.0/24 (via 172.16.60.1) further fragments forwarding. Fix: Remove redundant summary 172.158.0.0/23 and ensure all subnets within 172.158.0.0/22 use the same next-hop 192.168.98.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    31.69.215.0/25 [110/4] via 192.168.2.1, 00:01:18, GigabitEthernet0/0
C    192.168.231.0/24 is directly connected, GigabitEthernet0/0
O    107.126.166.0/23 [110/5] via 192.168.2.1, 00:03:27, GigabitEthernet0/0
O    102.174.0.0/18 [110/2] via 192.168.2.1, 00:04:29, GigabitEthernet0/0
O    10.211.1.0/24 [110/2] via 172.16.39.1, 00:05:47, GigabitEthernet0/0
S    10.211.0.0/22 [1/0] via 192.168.2.1
S    10.211.0.0/23 [1/0] via 10.0.37.1

Question: Identify all potential issues in this routing table and classify them by severity.

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 10.211.0.0/22 (S, via 192.168.2.1) and 10.211.0.0/23 (S, via 10.0.37.1).
2. Observation: Additionally, 10.211.1.0/24 is learned via OSPF through 172.16.39.1, and this /24 is contained within both summaries.
3. Analysis: 10.211.0.0/23 is completely contained within 10.211.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.2.1 vs 10.0.37.1). For traffic to 10.211.0.0/23, the more specific /23 route wins, sending traffic to 10.0.37.1. For traffic to 10.211.2.0/24 and 10.211.3.0/24, the /22 route applies, sending traffic to 192.168.2.1. The specific route 10.211.1.0/24 overrides both, sending traffic to 172.16.39.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 10.211.0.0/23 ⊂ 10.211.0.0/22, but next-hops differ. The specific route 10.211.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 10.211.0.0/23 if 10.211.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 10.211.0.0/22 (S, via 192.168.2.1) and 10.211.0.0/23 (S, via 10.0.37.1) overlap but have different next-hops. 10.211.1.0/24 (via 172.16.39.1) further fragments forwarding. Fix: Remove redundant summary 10.211.0.0/23 and ensure all subnets within 10.211.0.0/22 use the same next-hop 192.168.2.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    211.173.233.0/26 [110/3] via 192.168.180.1, 00:01:12, GigabitEthernet0/0
S    10.81.0.0/23 [1/0] via 10.0.186.1
O    223.67.114.0/26 [110/5] via 192.168.180.1, 00:01:41, GigabitEthernet0/0
O    153.239.252.208/28 [110/5] via 192.168.180.1, 00:03:20, GigabitEthernet0/0
S    10.81.0.0/22 [1/0] via 192.168.180.1
O    10.81.1.0/24 [110/2] via 172.16.230.1, 00:05:39, GigabitEthernet0/0
C    192.168.183.0/24 is directly connected, GigabitEthernet0/0
O    187.160.199.0/24 [110/4] via 192.168.180.1, 00:01:49, GigabitEthernet0/0

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 10.81.0.0/22 (S, via 192.168.180.1) and 10.81.0.0/23 (S, via 10.0.186.1).
2. Observation: Additionally, 10.81.1.0/24 is learned via OSPF through 172.16.230.1, and this /24 is contained within both summaries.
3. Analysis: 10.81.0.0/23 is completely contained within 10.81.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.180.1 vs 10.0.186.1). For traffic to 10.81.0.0/23, the more specific /23 route wins, sending traffic to 10.0.186.1. For traffic to 10.81.2.0/24 and 10.81.3.0/24, the /22 route applies, sending traffic to 192.168.180.1. The specific route 10.81.1.0/24 overrides both, sending traffic to 172.16.230.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 10.81.0.0/23 ⊂ 10.81.0.0/22, but next-hops differ. The specific route 10.81.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 10.81.0.0/23 if 10.81.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 10.81.0.0/22 (S, via 192.168.180.1) and 10.81.0.0/23 (S, via 10.0.186.1) overlap but have different next-hops. 10.81.1.0/24 (via 172.16.230.1) further fragments forwarding. Fix: Remove redundant summary 10.81.0.0/23 and ensure all subnets within 10.81.0.0/22 use the same next-hop 192.168.180.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    130.129.128.0/19 [110/3] via 192.168.44.1, 00:04:36, GigabitEthernet0/0
O    129.1.191.8/29 [110/5] via 192.168.44.1, 00:04:33, GigabitEthernet0/0
O    163.198.40.216/29 [110/4] via 192.168.44.1, 00:01:47, GigabitEthernet0/0
O*IA 10.54.0.0/22 [110/2] via 192.168.44.1, 00:02:11, GigabitEthernet0/0
C    192.168.10.0/24 is directly connected, GigabitEthernet0/0
O    10.54.0.0/23 [110/3] via 10.0.117.1, 00:04:25, GigabitEthernet0/1
O    10.54.1.0/24 [110/2] via 172.16.34.1, 00:05:20, GigabitEthernet0/0

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 10.54.0.0/22 (O*IA, via 192.168.44.1) and 10.54.0.0/23 (O, via 10.0.117.1).
2. Observation: Additionally, 10.54.1.0/24 is learned via OSPF through 172.16.34.1, and this /24 is contained within both summaries.
3. Analysis: 10.54.0.0/23 is completely contained within 10.54.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.44.1 vs 10.0.117.1). For traffic to 10.54.0.0/23, the more specific /23 route wins, sending traffic to 10.0.117.1. For traffic to 10.54.2.0/24 and 10.54.3.0/24, the /22 route applies, sending traffic to 192.168.44.1. The specific route 10.54.1.0/24 overrides both, sending traffic to 172.16.34.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 10.54.0.0/23 ⊂ 10.54.0.0/22, but next-hops differ. The specific route 10.54.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 10.54.0.0/23 if 10.54.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 10.54.0.0/22 (O*IA, via 192.168.44.1) and 10.54.0.0/23 (O, via 10.0.117.1) overlap but have different next-hops. 10.54.1.0/24 (via 172.16.34.1) further fragments forwarding. Fix: Remove redundant summary 10.54.0.0/23 and ensure all subnets within 10.54.0.0/22 use the same next-hop 192.168.44.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    10.157.1.0/24 [110/2] via 172.16.162.1, 00:02:45, GigabitEthernet0/0
O    136.225.104.0/21 [110/4] via 192.168.5.1, 00:03:57, GigabitEthernet0/0
S    10.157.0.0/22 [1/0] via 192.168.5.1
O    165.100.0.0/18 [110/3] via 192.168.5.1, 00:03:18, GigabitEthernet0/0
C    192.168.40.0/24 is directly connected, GigabitEthernet0/0
O    10.157.0.0/23 [110/3] via 10.0.140.1, 00:02:20, GigabitEthernet0/1
O    144.106.156.0/22 [110/2] via 192.168.5.1, 00:01:52, GigabitEthernet0/0

Question: Identify all potential issues in this routing table and classify them by severity.

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 10.157.0.0/22 (S, via 192.168.5.1) and 10.157.0.0/23 (O, via 10.0.140.1).
2. Observation: Additionally, 10.157.1.0/24 is learned via OSPF through 172.16.162.1, and this /24 is contained within both summaries.
3. Analysis: 10.157.0.0/23 is completely contained within 10.157.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.5.1 vs 10.0.140.1). For traffic to 10.157.0.0/23, the more specific /23 route wins, sending traffic to 10.0.140.1. For traffic to 10.157.2.0/24 and 10.157.3.0/24, the /22 route applies, sending traffic to 192.168.5.1. The specific route 10.157.1.0/24 overrides both, sending traffic to 172.16.162.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 10.157.0.0/23 ⊂ 10.157.0.0/22, but next-hops differ. The specific route 10.157.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 10.157.0.0/23 if 10.157.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 10.157.0.0/22 (S, via 192.168.5.1) and 10.157.0.0/23 (O, via 10.0.140.1) overlap but have different next-hops. 10.157.1.0/24 (via 172.16.162.1) further fragments forwarding. Fix: Remove redundant summary 10.157.0.0/23 and ensure all subnets within 10.157.0.0/22 use the same next-hop 192.168.5.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    22.117.116.192/26 [110/4] via 192.168.196.1, 00:04:57, GigabitEthernet0/0
C    192.168.209.0/24 is directly connected, GigabitEthernet0/0
S    172.160.0.0/23 [1/0] via 10.0.106.1
S    172.160.0.0/22 [1/0] via 192.168.196.1
O    172.160.1.0/24 [110/2] via 172.16.122.1, 00:01:56, GigabitEthernet0/0
O    87.74.200.64/28 [110/3] via 192.168.196.1, 00:05:39, GigabitEthernet0/0

Question: Identify all potential issues in this routing table and classify them by severity.

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 172.160.0.0/22 (S, via 192.168.196.1) and 172.160.0.0/23 (S, via 10.0.106.1).
2. Observation: Additionally, 172.160.1.0/24 is learned via OSPF through 172.16.122.1, and this /24 is contained within both summaries.
3. Analysis: 172.160.0.0/23 is completely contained within 172.160.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.196.1 vs 10.0.106.1). For traffic to 172.160.0.0/23, the more specific /23 route wins, sending traffic to 10.0.106.1. For traffic to 172.160.2.0/24 and 172.160.3.0/24, the /22 route applies, sending traffic to 192.168.196.1. The specific route 172.160.1.0/24 overrides both, sending traffic to 172.16.122.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 172.160.0.0/23 ⊂ 172.160.0.0/22, but next-hops differ. The specific route 172.160.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 172.160.0.0/23 if 172.160.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 172.160.0.0/22 (S, via 192.168.196.1) and 172.160.0.0/23 (S, via 10.0.106.1) overlap but have different next-hops. 172.160.1.0/24 (via 172.16.122.1) further fragments forwarding. Fix: Remove redundant summary 172.160.0.0/23 and ensure all subnets within 172.160.0.0/22 use the same next-hop 192.168.196.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    97.185.72.0/22 [110/2] via 192.168.178.1, 00:04:56, GigabitEthernet0/0
C    192.168.232.0/24 is directly connected, GigabitEthernet0/0
O    187.44.128.0/17 [110/4] via 192.168.178.1, 00:01:53, GigabitEthernet0/0
O    152.205.24.0/22 [110/5] via 192.168.178.1, 00:01:45, GigabitEthernet0/0
S    10.199.0.0/23 [1/0] via 10.0.150.1
O    10.199.1.0/24 [110/2] via 172.16.24.1, 00:05:45, GigabitEthernet0/0
S    10.199.0.0/22 [1/0] via 192.168.178.1

Question: Identify all potential issues in this routing table and classify them by severity.

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 10.199.0.0/22 (S, via 192.168.178.1) and 10.199.0.0/23 (S, via 10.0.150.1).
2. Observation: Additionally, 10.199.1.0/24 is learned via OSPF through 172.16.24.1, and this /24 is contained within both summaries.
3. Analysis: 10.199.0.0/23 is completely contained within 10.199.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.178.1 vs 10.0.150.1). For traffic to 10.199.0.0/23, the more specific /23 route wins, sending traffic to 10.0.150.1. For traffic to 10.199.2.0/24 and 10.199.3.0/24, the /22 route applies, sending traffic to 192.168.178.1. The specific route 10.199.1.0/24 overrides both, sending traffic to 172.16.24.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 10.199.0.0/23 ⊂ 10.199.0.0/22, but next-hops differ. The specific route 10.199.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 10.199.0.0/23 if 10.199.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 10.199.0.0/22 (S, via 192.168.178.1) and 10.199.0.0/23 (S, via 10.0.150.1) overlap but have different next-hops. 10.199.1.0/24 (via 172.16.24.1) further fragments forwarding. Fix: Remove redundant summary 10.199.0.0/23 and ensure all subnets within 10.199.0.0/22 use the same next-hop 192.168.178.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    155.2.30.48/28 [110/3] via 192.168.100.1, 00:02:16, GigabitEthernet0/0
O    172.148.1.0/24 [110/2] via 172.16.78.1, 00:02:18, GigabitEthernet0/0
C    192.168.74.0/24 is directly connected, GigabitEthernet0/0
O    57.141.35.208/28 [110/4] via 192.168.100.1, 00:05:37, GigabitEthernet0/0
O    42.84.37.152/29 [110/5] via 192.168.100.1, 00:01:47, GigabitEthernet0/0
O*IA 172.148.0.0/22 [110/2] via 192.168.100.1, 00:03:52, GigabitEthernet0/0
S    172.148.0.0/23 [1/0] via 10.0.228.1

Question: Does this routing table have any routing inconsistencies?

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 172.148.0.0/22 (O*IA, via 192.168.100.1) and 172.148.0.0/23 (S, via 10.0.228.1).
2. Observation: Additionally, 172.148.1.0/24 is learned via OSPF through 172.16.78.1, and this /24 is contained within both summaries.
3. Analysis: 172.148.0.0/23 is completely contained within 172.148.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.100.1 vs 10.0.228.1). For traffic to 172.148.0.0/23, the more specific /23 route wins, sending traffic to 10.0.228.1. For traffic to 172.148.2.0/24 and 172.148.3.0/24, the /22 route applies, sending traffic to 192.168.100.1. The specific route 172.148.1.0/24 overrides both, sending traffic to 172.16.78.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 172.148.0.0/23 ⊂ 172.148.0.0/22, but next-hops differ. The specific route 172.148.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 172.148.0.0/23 if 172.148.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 172.148.0.0/22 (O*IA, via 192.168.100.1) and 172.148.0.0/23 (S, via 10.0.228.1) overlap but have different next-hops. 172.148.1.0/24 (via 172.16.78.1) further fragments forwarding. Fix: Remove redundant summary 172.148.0.0/23 and ensure all subnets within 172.148.0.0/22 use the same next-hop 192.168.100.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    146.174.24.64/26 [110/2] via 192.168.124.1, 00:03:19, GigabitEthernet0/0
O    10.125.1.0/24 [110/2] via 172.16.181.1, 00:04:56, GigabitEthernet0/0
O    88.148.72.200/30 [110/5] via 192.168.124.1, 00:02:20, GigabitEthernet0/0
O    31.5.132.104/29 [110/2] via 192.168.124.1, 00:04:51, GigabitEthernet0/0
O    166.142.112.0/21 [110/3] via 192.168.124.1, 00:02:27, GigabitEthernet0/0
S    10.125.0.0/22 [1/0] via 192.168.124.1
O    10.125.0.0/23 [110/3] via 10.0.206.1, 00:05:48, GigabitEthernet0/1
C    192.168.65.0/24 is directly connected, GigabitEthernet0/0

Question: Are there any overlapping networks in this routing table?

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 10.125.0.0/22 (S, via 192.168.124.1) and 10.125.0.0/23 (O, via 10.0.206.1).
2. Observation: Additionally, 10.125.1.0/24 is learned via OSPF through 172.16.181.1, and this /24 is contained within both summaries.
3. Analysis: 10.125.0.0/23 is completely contained within 10.125.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.124.1 vs 10.0.206.1). For traffic to 10.125.0.0/23, the more specific /23 route wins, sending traffic to 10.0.206.1. For traffic to 10.125.2.0/24 and 10.125.3.0/24, the /22 route applies, sending traffic to 192.168.124.1. The specific route 10.125.1.0/24 overrides both, sending traffic to 172.16.181.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 10.125.0.0/23 ⊂ 10.125.0.0/22, but next-hops differ. The specific route 10.125.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 10.125.0.0/23 if 10.125.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 10.125.0.0/22 (S, via 192.168.124.1) and 10.125.0.0/23 (O, via 10.0.206.1) overlap but have different next-hops. 10.125.1.0/24 (via 172.16.181.1) further fragments forwarding. Fix: Remove redundant summary 10.125.0.0/23 and ensure all subnets within 10.125.0.0/22 use the same next-hop 192.168.124.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    125.149.93.0/26 [110/5] via 192.168.9.1, 00:05:35, GigabitEthernet0/0
C    192.168.1.0/24 is directly connected, GigabitEthernet0/0
S    172.82.0.0/22 [1/0] via 192.168.9.1
O    172.82.1.0/24 [110/2] via 172.16.72.1, 00:01:16, GigabitEthernet0/0
S    172.82.0.0/23 [1/0] via 10.0.32.1
O    205.32.147.0/26 [110/2] via 192.168.9.1, 00:02:11, GigabitEthernet0/0

Question: Does this routing table have any routing inconsistencies?

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 172.82.0.0/22 (S, via 192.168.9.1) and 172.82.0.0/23 (S, via 10.0.32.1).
2. Observation: Additionally, 172.82.1.0/24 is learned via OSPF through 172.16.72.1, and this /24 is contained within both summaries.
3. Analysis: 172.82.0.0/23 is completely contained within 172.82.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.9.1 vs 10.0.32.1). For traffic to 172.82.0.0/23, the more specific /23 route wins, sending traffic to 10.0.32.1. For traffic to 172.82.2.0/24 and 172.82.3.0/24, the /22 route applies, sending traffic to 192.168.9.1. The specific route 172.82.1.0/24 overrides both, sending traffic to 172.16.72.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 172.82.0.0/23 ⊂ 172.82.0.0/22, but next-hops differ. The specific route 172.82.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 172.82.0.0/23 if 172.82.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 172.82.0.0/22 (S, via 192.168.9.1) and 172.82.0.0/23 (S, via 10.0.32.1) overlap but have different next-hops. 172.82.1.0/24 (via 172.16.72.1) further fragments forwarding. Fix: Remove redundant summary 172.82.0.0/23 and ensure all subnets within 172.82.0.0/22 use the same next-hop 192.168.9.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
S    172.109.0.0/22 [1/0] via 192.168.110.1
O    172.109.1.0/24 [110/2] via 172.16.175.1, 00:04:12, GigabitEthernet0/0
O    64.250.0.0/16 [110/2] via 192.168.110.1, 00:01:47, GigabitEthernet0/0
C    192.168.158.0/24 is directly connected, GigabitEthernet0/0
O    193.63.128.0/18 [110/5] via 192.168.110.1, 00:03:58, GigabitEthernet0/0
S    172.109.0.0/23 [1/0] via 10.0.222.1

Question: Are there any overlapping networks in this routing table?

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 172.109.0.0/22 (S, via 192.168.110.1) and 172.109.0.0/23 (S, via 10.0.222.1).
2. Observation: Additionally, 172.109.1.0/24 is learned via OSPF through 172.16.175.1, and this /24 is contained within both summaries.
3. Analysis: 172.109.0.0/23 is completely contained within 172.109.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.110.1 vs 10.0.222.1). For traffic to 172.109.0.0/23, the more specific /23 route wins, sending traffic to 10.0.222.1. For traffic to 172.109.2.0/24 and 172.109.3.0/24, the /22 route applies, sending traffic to 192.168.110.1. The specific route 172.109.1.0/24 overrides both, sending traffic to 172.16.175.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 172.109.0.0/23 ⊂ 172.109.0.0/22, but next-hops differ. The specific route 172.109.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 172.109.0.0/23 if 172.109.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 172.109.0.0/22 (S, via 192.168.110.1) and 172.109.0.0/23 (S, via 10.0.222.1) overlap but have different next-hops. 172.109.1.0/24 (via 172.16.175.1) further fragments forwarding. Fix: Remove redundant summary 172.109.0.0/23 and ensure all subnets within 172.109.0.0/22 use the same next-hop 192.168.110.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    10.248.1.0/24 [110/2] via 172.16.252.1, 00:05:58, GigabitEthernet0/0
O    190.113.160.0/19 [110/3] via 192.168.134.1, 00:02:19, GigabitEthernet0/0
O    10.248.0.0/23 [110/3] via 10.0.57.1, 00:02:25, GigabitEthernet0/1
O    60.243.192.0/18 [110/5] via 192.168.134.1, 00:03:10, GigabitEthernet0/0
O    201.18.168.0/24 [110/3] via 192.168.134.1, 00:05:31, GigabitEthernet0/0
S    10.248.0.0/22 [1/0] via 192.168.134.1
C    192.168.12.0/24 is directly connected, GigabitEthernet0/0

Question: Does this routing table have any routing inconsistencies?

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 10.248.0.0/22 (S, via 192.168.134.1) and 10.248.0.0/23 (O, via 10.0.57.1).
2. Observation: Additionally, 10.248.1.0/24 is learned via OSPF through 172.16.252.1, and this /24 is contained within both summaries.
3. Analysis: 10.248.0.0/23 is completely contained within 10.248.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.134.1 vs 10.0.57.1). For traffic to 10.248.0.0/23, the more specific /23 route wins, sending traffic to 10.0.57.1. For traffic to 10.248.2.0/24 and 10.248.3.0/24, the /22 route applies, sending traffic to 192.168.134.1. The specific route 10.248.1.0/24 overrides both, sending traffic to 172.16.252.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 10.248.0.0/23 ⊂ 10.248.0.0/22, but next-hops differ. The specific route 10.248.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 10.248.0.0/23 if 10.248.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 10.248.0.0/22 (S, via 192.168.134.1) and 10.248.0.0/23 (O, via 10.0.57.1) overlap but have different next-hops. 10.248.1.0/24 (via 172.16.252.1) further fragments forwarding. Fix: Remove redundant summary 10.248.0.0/23 and ensure all subnets within 10.248.0.0/22 use the same next-hop 192.168.134.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    164.155.0.0/16 [110/3] via 192.168.249.1, 00:02:33, GigabitEthernet0/0
S    172.175.0.0/22 [1/0] via 192.168.249.1
O    172.175.1.0/24 [110/2] via 172.16.240.1, 00:05:31, GigabitEthernet0/0
O    84.193.248.0/21 [110/2] via 192.168.249.1, 00:03:37, GigabitEthernet0/0
C    192.168.159.0/24 is directly connected, GigabitEthernet0/0
O    113.104.64.0/19 [110/3] via 192.168.249.1, 00:01:15, GigabitEthernet0/0
O    172.175.0.0/23 [110/3] via 10.0.30.1, 00:05:43, GigabitEthernet0/1

Question: Are there any overlapping networks in this routing table?

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 172.175.0.0/22 (S, via 192.168.249.1) and 172.175.0.0/23 (O, via 10.0.30.1).
2. Observation: Additionally, 172.175.1.0/24 is learned via OSPF through 172.16.240.1, and this /24 is contained within both summaries.
3. Analysis: 172.175.0.0/23 is completely contained within 172.175.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.249.1 vs 10.0.30.1). For traffic to 172.175.0.0/23, the more specific /23 route wins, sending traffic to 10.0.30.1. For traffic to 172.175.2.0/24 and 172.175.3.0/24, the /22 route applies, sending traffic to 192.168.249.1. The specific route 172.175.1.0/24 overrides both, sending traffic to 172.16.240.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 172.175.0.0/23 ⊂ 172.175.0.0/22, but next-hops differ. The specific route 172.175.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 172.175.0.0/23 if 172.175.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 172.175.0.0/22 (S, via 192.168.249.1) and 172.175.0.0/23 (O, via 10.0.30.1) overlap but have different next-hops. 172.175.1.0/24 (via 172.16.240.1) further fragments forwarding. Fix: Remove redundant summary 172.175.0.0/23 and ensure all subnets within 172.175.0.0/22 use the same next-hop 192.168.249.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
C    192.168.188.0/24 is directly connected, GigabitEthernet0/0
O*IA 10.45.0.0/22 [110/2] via 192.168.163.1, 00:01:34, GigabitEthernet0/0
O    187.30.118.0/28 [110/5] via 192.168.163.1, 00:04:14, GigabitEthernet0/0
O    92.44.48.0/20 [110/3] via 192.168.163.1, 00:03:28, GigabitEthernet0/0
S    10.45.0.0/23 [1/0] via 10.0.215.1
O    10.45.1.0/24 [110/2] via 172.16.236.1, 00:02:44, GigabitEthernet0/0

Question: Are there any overlapping networks in this routing table?

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 10.45.0.0/22 (O*IA, via 192.168.163.1) and 10.45.0.0/23 (S, via 10.0.215.1).
2. Observation: Additionally, 10.45.1.0/24 is learned via OSPF through 172.16.236.1, and this /24 is contained within both summaries.
3. Analysis: 10.45.0.0/23 is completely contained within 10.45.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.163.1 vs 10.0.215.1). For traffic to 10.45.0.0/23, the more specific /23 route wins, sending traffic to 10.0.215.1. For traffic to 10.45.2.0/24 and 10.45.3.0/24, the /22 route applies, sending traffic to 192.168.163.1. The specific route 10.45.1.0/24 overrides both, sending traffic to 172.16.236.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 10.45.0.0/23 ⊂ 10.45.0.0/22, but next-hops differ. The specific route 10.45.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 10.45.0.0/23 if 10.45.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 10.45.0.0/22 (O*IA, via 192.168.163.1) and 10.45.0.0/23 (S, via 10.0.215.1) overlap but have different next-hops. 10.45.1.0/24 (via 172.16.236.1) further fragments forwarding. Fix: Remove redundant summary 10.45.0.0/23 and ensure all subnets within 10.45.0.0/22 use the same next-hop 192.168.163.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    10.99.1.0/24 [110/2] via 172.16.155.1, 00:03:44, GigabitEthernet0/0
O    10.99.0.0/23 [110/3] via 10.0.227.1, 00:05:16, GigabitEthernet0/1
O*IA 10.99.0.0/22 [110/2] via 192.168.33.1, 00:04:42, GigabitEthernet0/0
C    192.168.232.0/24 is directly connected, GigabitEthernet0/0
O    12.141.190.80/28 [110/5] via 192.168.33.1, 00:03:34, GigabitEthernet0/0
O    24.23.24.224/27 [110/3] via 192.168.33.1, 00:03:44, GigabitEthernet0/0
O    142.61.24.0/21 [110/2] via 192.168.33.1, 00:01:56, GigabitEthernet0/0
O    187.223.247.0/26 [110/4] via 192.168.33.1, 00:04:49, GigabitEthernet0/0

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 10.99.0.0/22 (O*IA, via 192.168.33.1) and 10.99.0.0/23 (O, via 10.0.227.1).
2. Observation: Additionally, 10.99.1.0/24 is learned via OSPF through 172.16.155.1, and this /24 is contained within both summaries.
3. Analysis: 10.99.0.0/23 is completely contained within 10.99.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.33.1 vs 10.0.227.1). For traffic to 10.99.0.0/23, the more specific /23 route wins, sending traffic to 10.0.227.1. For traffic to 10.99.2.0/24 and 10.99.3.0/24, the /22 route applies, sending traffic to 192.168.33.1. The specific route 10.99.1.0/24 overrides both, sending traffic to 172.16.155.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 10.99.0.0/23 ⊂ 10.99.0.0/22, but next-hops differ. The specific route 10.99.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 10.99.0.0/23 if 10.99.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 10.99.0.0/22 (O*IA, via 192.168.33.1) and 10.99.0.0/23 (O, via 10.0.227.1) overlap but have different next-hops. 10.99.1.0/24 (via 172.16.155.1) further fragments forwarding. Fix: Remove redundant summary 10.99.0.0/23 and ensure all subnets within 10.99.0.0/22 use the same next-hop 192.168.33.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    10.205.0.0/23 [110/3] via 10.0.99.1, 00:03:56, GigabitEthernet0/1
O    10.205.1.0/24 [110/2] via 172.16.31.1, 00:01:20, GigabitEthernet0/0
S    10.205.0.0/22 [1/0] via 192.168.5.1
O    163.99.14.0/23 [110/4] via 192.168.5.1, 00:04:53, GigabitEthernet0/0
O    11.104.152.0/23 [110/3] via 192.168.5.1, 00:01:17, GigabitEthernet0/0
C    192.168.204.0/24 is directly connected, GigabitEthernet0/0

Question: Identify all potential issues in this routing table and classify them by severity.

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 10.205.0.0/22 (S, via 192.168.5.1) and 10.205.0.0/23 (O, via 10.0.99.1).
2. Observation: Additionally, 10.205.1.0/24 is learned via OSPF through 172.16.31.1, and this /24 is contained within both summaries.
3. Analysis: 10.205.0.0/23 is completely contained within 10.205.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.5.1 vs 10.0.99.1). For traffic to 10.205.0.0/23, the more specific /23 route wins, sending traffic to 10.0.99.1. For traffic to 10.205.2.0/24 and 10.205.3.0/24, the /22 route applies, sending traffic to 192.168.5.1. The specific route 10.205.1.0/24 overrides both, sending traffic to 172.16.31.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 10.205.0.0/23 ⊂ 10.205.0.0/22, but next-hops differ. The specific route 10.205.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 10.205.0.0/23 if 10.205.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 10.205.0.0/22 (S, via 192.168.5.1) and 10.205.0.0/23 (O, via 10.0.99.1) overlap but have different next-hops. 10.205.1.0/24 (via 172.16.31.1) further fragments forwarding. Fix: Remove redundant summary 10.205.0.0/23 and ensure all subnets within 10.205.0.0/22 use the same next-hop 192.168.5.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    172.124.1.0/24 [110/2] via 172.16.154.1, 00:04:42, GigabitEthernet0/0
O    120.50.86.204/30 [110/3] via 192.168.154.1, 00:05:23, GigabitEthernet0/0
O    198.53.32.0/20 [110/5] via 192.168.154.1, 00:01:28, GigabitEthernet0/0
O    136.85.128.0/23 [110/5] via 192.168.154.1, 00:04:59, GigabitEthernet0/0
S    172.124.0.0/22 [1/0] via 192.168.154.1
C    192.168.75.0/24 is directly connected, GigabitEthernet0/0
S    172.124.0.0/23 [1/0] via 10.0.184.1

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains overlapping summary routes: 172.124.0.0/22 (S, via 192.168.154.1) and 172.124.0.0/23 (S, via 10.0.184.1).
2. Observation: Additionally, 172.124.1.0/24 is learned via OSPF through 172.16.154.1, and this /24 is contained within both summaries.
3. Analysis: 172.124.0.0/23 is completely contained within 172.124.0.0/22 (/23 is a subset of /22). However, they have different next-hops (192.168.154.1 vs 10.0.184.1). For traffic to 172.124.0.0/23, the more specific /23 route wins, sending traffic to 10.0.184.1. For traffic to 172.124.2.0/24 and 172.124.3.0/24, the /22 route applies, sending traffic to 192.168.154.1. The specific route 172.124.1.0/24 overrides both, sending traffic to 172.16.154.1.
4. Impact: Overlapping summaries with different next-hops create fragmented and unpredictable forwarding behavior. Traffic to adjacent subnets within the same summary range may take completely different paths. This complicates troubleshooting, breaks stateful firewall sessions, and can cause asymmetric routing.
5. Detection: Prefix containment check shows 172.124.0.0/23 ⊂ 172.124.0.0/22, but next-hops differ. The specific route 172.124.1.0/24 further fragments the forwarding logic.
6. Recommendation: Consolidate all overlapping summaries into a single summary with one next-hop. If multiple egress points are needed, use more specific routes (not overlapping summaries) or implement policy-based routing. Remove redundant summary 172.124.0.0/23 if 172.124.0.0/22 already covers the range.
</reasoning>
<answer>
WARNING: Overlapping summary routes detected. 172.124.0.0/22 (S, via 192.168.154.1) and 172.124.0.0/23 (S, via 10.0.184.1) overlap but have different next-hops. 172.124.1.0/24 (via 172.16.154.1) further fragments forwarding. Fix: Remove redundant summary 172.124.0.0/23 and ensure all subnets within 172.124.0.0/22 use the same next-hop 192.168.154.1, or restructure into non-overlapping specific routes. Verify consistent path selection across the entire address range.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
C    192.168.60.0/24 is directly connected, GigabitEthernet0/0
O    172.166.0.0/24 [110/3] via 10.0.238.1, 00:03:29, GigabitEthernet0/1
O    125.119.128.0/18 [110/2] via 10.0.206.1, 00:04:17, GigabitEthernet0/0
O    172.166.2.0/24 [110/5] via 10.0.34.1, 00:01:48, GigabitEthernet0/1
O    172.166.1.0/24 [110/3] via 10.0.48.1, 00:02:27, GigabitEthernet0/1
O    172.166.3.0/24 [110/2] via 10.0.213.1, 00:01:16, GigabitEthernet0/1
S    172.166.0.0/22 [1/0] via 192.168.24.1
O    119.210.16.0/22 [110/3] via 10.0.178.1, 00:04:58, GigabitEthernet0/0

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.166.0.0/22 (S, via 192.168.24.1).
2. Observation: Only 4 specific routes exist within this summary: 172.166.0.0/24, 172.166.1.0/24, 172.166.2.0/24, 172.166.3.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 0 missing subnets between them (gaps at subnets []).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.24.1 and potentially black-holed.
5. Impact: Traffic to any of the 0 gap subnets (e.g., ) will follow the summary route to 192.168.24.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 172.166.0.0/22 are at non-contiguous positions ([0, 1, 2, 3]), leaving 0 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 172.166.0.0/22, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 172.166.0.0/22 covers a range with 0 gaps (missing subnets like ). Traffic to non-existent gap subnets will be black-holed at 192.168.24.1. Fix: Split 172.166.0.0/22 into smaller, non-overlapping summaries that exactly cover only the 4 existing subnets (172.166.0.0/24, 172.166.1.0/24, 172.166.2.0/24, 172.166.3.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O*IA 172.32.0.0/22 [110/2] via 192.168.237.1, 00:02:12, GigabitEthernet0/0
O    105.95.32.0/20 [110/4] via 10.0.247.1, 00:03:39, GigabitEthernet0/0
O    172.32.1.0/24 [110/4] via 10.0.161.1, 00:05:57, GigabitEthernet0/1
O    53.28.186.64/26 [110/4] via 10.0.127.1, 00:02:45, GigabitEthernet0/0
C    192.168.111.0/24 is directly connected, GigabitEthernet0/0
O    172.32.3.0/24 [110/5] via 10.0.236.1, 00:02:55, GigabitEthernet0/1
O    172.32.2.0/24 [110/5] via 10.0.3.1, 00:01:54, GigabitEthernet0/1
O    32.168.183.32/29 [110/3] via 10.0.58.1, 00:04:41, GigabitEthernet0/0
O    10.11.128.0/17 [110/5] via 10.0.30.1, 00:03:53, GigabitEthernet0/0

Question: Does this routing table contain any routing blackholes?

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.32.0.0/22 (O*IA, via 192.168.237.1).
2. Observation: Only 3 specific routes exist within this summary: 172.32.1.0/24, 172.32.2.0/24, 172.32.3.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 1 missing subnets between them (gaps at subnets [0]).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.237.1 and potentially black-holed.
5. Impact: Traffic to any of the 1 gap subnets (e.g., 172.32.0.0/24) will follow the summary route to 192.168.237.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 172.32.0.0/22 are at non-contiguous positions ([1, 2, 3]), leaving 1 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 172.32.0.0/22, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 172.32.0.0/22 covers a range with 1 gaps (missing subnets like 172.32.0.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.237.1. Fix: Split 172.32.0.0/22 into smaller, non-overlapping summaries that exactly cover only the 3 existing subnets (172.32.1.0/24, 172.32.2.0/24, 172.32.3.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    70.141.39.160/28 [110/5] via 10.0.250.1, 00:02:20, GigabitEthernet0/0
O    172.61.7.0/24 [110/5] via 10.0.200.1, 00:03:12, GigabitEthernet0/1
C    192.168.99.0/24 is directly connected, GigabitEthernet0/0
O    71.227.0.0/16 [110/2] via 10.0.207.1, 00:03:55, GigabitEthernet0/0
O    172.61.6.0/24 [110/2] via 10.0.211.1, 00:04:14, GigabitEthernet0/1
O    39.12.210.0/24 [110/4] via 10.0.148.1, 00:04:38, GigabitEthernet0/0
S    172.61.0.0/21 [1/0] via 192.168.214.1
O    140.43.192.0/19 [110/2] via 10.0.164.1, 00:02:17, GigabitEthernet0/0

Question: Analyze this routing table for traffic blackholing risks.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.61.0.0/21 (S, via 192.168.214.1).
2. Observation: Only 2 specific routes exist within this summary: 172.61.6.0/24, 172.61.7.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 6 missing subnets between them (gaps at subnets [0, 1, 2, 3, 4]...).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.214.1 and potentially black-holed.
5. Impact: Traffic to any of the 6 gap subnets (e.g., 172.61.0.0/24, 172.61.1.0/24) will follow the summary route to 192.168.214.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 172.61.0.0/21 are at non-contiguous positions ([6, 7]), leaving 6 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 172.61.0.0/21, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 172.61.0.0/21 covers a range with 6 gaps (missing subnets like 172.61.0.0/24, 172.61.1.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.214.1. Fix: Split 172.61.0.0/21 into smaller, non-overlapping summaries that exactly cover only the 2 existing subnets (172.61.6.0/24, 172.61.7.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    172.153.14.0/24 [110/2] via 10.0.163.1, 00:03:33, GigabitEthernet0/1
C    192.168.220.0/24 is directly connected, GigabitEthernet0/0
O    172.153.12.0/24 [110/5] via 10.0.88.1, 00:01:23, GigabitEthernet0/1
O    172.153.4.0/24 [110/4] via 10.0.10.1, 00:01:55, GigabitEthernet0/1
S    172.153.0.0/20 [1/0] via 192.168.39.1
O    161.119.0.0/18 [110/2] via 10.0.120.1, 00:03:14, GigabitEthernet0/0
O    86.60.48.0/20 [110/3] via 10.0.143.1, 00:03:21, GigabitEthernet0/0
O    43.94.0.0/16 [110/4] via 10.0.113.1, 00:05:25, GigabitEthernet0/0

Question: Identify all potential issues in this routing table and classify them by severity.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.153.0.0/20 (S, via 192.168.39.1).
2. Observation: Only 3 specific routes exist within this summary: 172.153.4.0/24, 172.153.12.0/24, 172.153.14.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 13 missing subnets between them (gaps at subnets [0, 1, 2, 3, 5]...).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.39.1 and potentially black-holed.
5. Impact: Traffic to any of the 13 gap subnets (e.g., 172.153.0.0/24, 172.153.1.0/24) will follow the summary route to 192.168.39.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 172.153.0.0/20 are at non-contiguous positions ([4, 12, 14]), leaving 13 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 172.153.0.0/20, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 172.153.0.0/20 covers a range with 13 gaps (missing subnets like 172.153.0.0/24, 172.153.1.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.39.1. Fix: Split 172.153.0.0/20 into smaller, non-overlapping summaries that exactly cover only the 3 existing subnets (172.153.4.0/24, 172.153.12.0/24, 172.153.14.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    172.172.10.0/24 [110/3] via 10.0.149.1, 00:02:22, GigabitEthernet0/1
O*IA 172.172.0.0/20 [110/2] via 192.168.173.1, 00:05:31, GigabitEthernet0/0
O    172.172.14.0/24 [110/4] via 10.0.232.1, 00:01:37, GigabitEthernet0/1
O    194.0.222.0/23 [110/2] via 10.0.248.1, 00:01:44, GigabitEthernet0/0
C    192.168.107.0/24 is directly connected, GigabitEthernet0/0
O    97.160.50.0/25 [110/4] via 10.0.241.1, 00:04:22, GigabitEthernet0/0
O    172.172.11.0/24 [110/2] via 10.0.54.1, 00:05:14, GigabitEthernet0/1
O    212.218.32.0/19 [110/4] via 10.0.244.1, 00:01:11, GigabitEthernet0/0
O    162.123.148.192/28 [110/5] via 10.0.66.1, 00:01:52, GigabitEthernet0/0
O    172.172.1.0/24 [110/4] via 10.0.30.1, 00:01:39, GigabitEthernet0/1

Question: Does this routing table contain any routing blackholes?

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.172.0.0/20 (O*IA, via 192.168.173.1).
2. Observation: Only 4 specific routes exist within this summary: 172.172.1.0/24, 172.172.10.0/24, 172.172.11.0/24, 172.172.14.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 12 missing subnets between them (gaps at subnets [0, 2, 3, 4, 5]...).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.173.1 and potentially black-holed.
5. Impact: Traffic to any of the 12 gap subnets (e.g., 172.172.0.0/24, 172.172.2.0/24) will follow the summary route to 192.168.173.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 172.172.0.0/20 are at non-contiguous positions ([1, 10, 11, 14]), leaving 12 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 172.172.0.0/20, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 172.172.0.0/20 covers a range with 12 gaps (missing subnets like 172.172.0.0/24, 172.172.2.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.173.1. Fix: Split 172.172.0.0/20 into smaller, non-overlapping summaries that exactly cover only the 4 existing subnets (172.172.1.0/24, 172.172.10.0/24, 172.172.11.0/24, 172.172.14.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    94.248.0.0/20 [110/2] via 10.0.105.1, 00:02:46, GigabitEthernet0/0
O    10.101.0.0/24 [110/4] via 10.0.87.1, 00:04:29, GigabitEthernet0/1
O    144.246.45.64/30 [110/2] via 10.0.253.1, 00:05:22, GigabitEthernet0/0
C    192.168.216.0/24 is directly connected, GigabitEthernet0/0
O    10.101.7.0/24 [110/5] via 10.0.161.1, 00:02:37, GigabitEthernet0/1
O    10.101.5.0/24 [110/2] via 10.0.77.1, 00:01:26, GigabitEthernet0/1
S    10.101.0.0/21 [1/0] via 192.168.45.1
O    10.101.4.0/24 [110/2] via 10.0.250.1, 00:02:54, GigabitEthernet0/1

Question: Identify all potential issues in this routing table and classify them by severity.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 10.101.0.0/21 (S, via 192.168.45.1).
2. Observation: Only 4 specific routes exist within this summary: 10.101.0.0/24, 10.101.4.0/24, 10.101.5.0/24, 10.101.7.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 4 missing subnets between them (gaps at subnets [1, 2, 3, 6]).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.45.1 and potentially black-holed.
5. Impact: Traffic to any of the 4 gap subnets (e.g., 10.101.1.0/24, 10.101.2.0/24) will follow the summary route to 192.168.45.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 10.101.0.0/21 are at non-contiguous positions ([0, 4, 5, 7]), leaving 4 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 10.101.0.0/21, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 10.101.0.0/21 covers a range with 4 gaps (missing subnets like 10.101.1.0/24, 10.101.2.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.45.1. Fix: Split 10.101.0.0/21 into smaller, non-overlapping summaries that exactly cover only the 4 existing subnets (10.101.0.0/24, 10.101.4.0/24, 10.101.5.0/24, 10.101.7.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
C    192.168.171.0/24 is directly connected, GigabitEthernet0/0
S    10.223.0.0/22 [1/0] via 192.168.156.1
O    37.34.192.0/18 [110/5] via 10.0.217.1, 00:03:31, GigabitEthernet0/0
O    10.223.2.0/24 [110/4] via 10.0.129.1, 00:02:33, GigabitEthernet0/1
O    10.223.0.0/24 [110/3] via 10.0.125.1, 00:03:13, GigabitEthernet0/1
O    49.45.219.0/24 [110/4] via 10.0.144.1, 00:05:30, GigabitEthernet0/0
O    173.208.197.0/24 [110/3] via 10.0.11.1, 00:05:55, GigabitEthernet0/0
O    107.144.16.0/20 [110/2] via 10.0.81.1, 00:02:44, GigabitEthernet0/0

Question: Does this routing table contain any routing blackholes?

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 10.223.0.0/22 (S, via 192.168.156.1).
2. Observation: Only 2 specific routes exist within this summary: 10.223.0.0/24, 10.223.2.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 2 missing subnets between them (gaps at subnets [1, 3]).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.156.1 and potentially black-holed.
5. Impact: Traffic to any of the 2 gap subnets (e.g., 10.223.1.0/24, 10.223.3.0/24) will follow the summary route to 192.168.156.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 10.223.0.0/22 are at non-contiguous positions ([0, 2]), leaving 2 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 10.223.0.0/22, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 10.223.0.0/22 covers a range with 2 gaps (missing subnets like 10.223.1.0/24, 10.223.3.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.156.1. Fix: Split 10.223.0.0/22 into smaller, non-overlapping summaries that exactly cover only the 2 existing subnets (10.223.0.0/24, 10.223.2.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    165.143.0.0/17 [110/5] via 10.0.213.1, 00:03:36, GigabitEthernet0/0
O*IA 172.68.0.0/22 [110/2] via 192.168.147.1, 00:02:33, GigabitEthernet0/0
O    101.249.128.0/18 [110/4] via 10.0.220.1, 00:03:22, GigabitEthernet0/0
C    192.168.135.0/24 is directly connected, GigabitEthernet0/0
O    56.231.112.0/21 [110/4] via 10.0.219.1, 00:01:20, GigabitEthernet0/0
O    172.68.3.0/24 [110/3] via 10.0.90.1, 00:01:45, GigabitEthernet0/1
O    172.68.1.0/24 [110/5] via 10.0.206.1, 00:01:16, GigabitEthernet0/1
O    27.75.160.0/19 [110/2] via 10.0.240.1, 00:01:16, GigabitEthernet0/0

Question: Analyze this routing table for traffic blackholing risks.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.68.0.0/22 (O*IA, via 192.168.147.1).
2. Observation: Only 2 specific routes exist within this summary: 172.68.1.0/24, 172.68.3.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 2 missing subnets between them (gaps at subnets [0, 2]).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.147.1 and potentially black-holed.
5. Impact: Traffic to any of the 2 gap subnets (e.g., 172.68.0.0/24, 172.68.2.0/24) will follow the summary route to 192.168.147.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 172.68.0.0/22 are at non-contiguous positions ([1, 3]), leaving 2 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 172.68.0.0/22, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 172.68.0.0/22 covers a range with 2 gaps (missing subnets like 172.68.0.0/24, 172.68.2.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.147.1. Fix: Split 172.68.0.0/22 into smaller, non-overlapping summaries that exactly cover only the 2 existing subnets (172.68.1.0/24, 172.68.3.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    10.163.3.0/24 [110/3] via 10.0.239.1, 00:02:14, GigabitEthernet0/1
O    10.163.1.0/24 [110/5] via 10.0.91.1, 00:02:22, GigabitEthernet0/1
O    10.163.0.0/24 [110/2] via 10.0.28.1, 00:01:30, GigabitEthernet0/1
O    108.175.0.0/17 [110/2] via 10.0.107.1, 00:02:41, GigabitEthernet0/0
O    197.4.224.0/19 [110/2] via 10.0.232.1, 00:03:25, GigabitEthernet0/0
O*IA 10.163.0.0/22 [110/2] via 192.168.203.1, 00:03:32, GigabitEthernet0/0
O    10.163.2.0/24 [110/3] via 10.0.186.1, 00:04:50, GigabitEthernet0/1
C    192.168.10.0/24 is directly connected, GigabitEthernet0/0

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 10.163.0.0/22 (O*IA, via 192.168.203.1).
2. Observation: Only 4 specific routes exist within this summary: 10.163.0.0/24, 10.163.1.0/24, 10.163.2.0/24, 10.163.3.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 0 missing subnets between them (gaps at subnets []).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.203.1 and potentially black-holed.
5. Impact: Traffic to any of the 0 gap subnets (e.g., ) will follow the summary route to 192.168.203.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 10.163.0.0/22 are at non-contiguous positions ([0, 1, 2, 3]), leaving 0 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 10.163.0.0/22, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 10.163.0.0/22 covers a range with 0 gaps (missing subnets like ). Traffic to non-existent gap subnets will be black-holed at 192.168.203.1. Fix: Split 10.163.0.0/22 into smaller, non-overlapping summaries that exactly cover only the 4 existing subnets (10.163.0.0/24, 10.163.1.0/24, 10.163.2.0/24, 10.163.3.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    172.63.1.0/24 [110/5] via 10.0.71.1, 00:05:17, GigabitEthernet0/1
O    212.65.0.0/17 [110/3] via 10.0.121.1, 00:02:53, GigabitEthernet0/0
O    172.63.0.0/24 [110/2] via 10.0.24.1, 00:01:48, GigabitEthernet0/1
O    57.145.0.0/16 [110/5] via 10.0.53.1, 00:04:21, GigabitEthernet0/0
C    192.168.27.0/24 is directly connected, GigabitEthernet0/0
S    172.63.0.0/20 [1/0] via 192.168.240.1

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.63.0.0/20 (S, via 192.168.240.1).
2. Observation: Only 2 specific routes exist within this summary: 172.63.0.0/24, 172.63.1.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 14 missing subnets between them (gaps at subnets [2, 3, 4, 5, 6]...).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.240.1 and potentially black-holed.
5. Impact: Traffic to any of the 14 gap subnets (e.g., 172.63.2.0/24, 172.63.3.0/24) will follow the summary route to 192.168.240.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 172.63.0.0/20 are at non-contiguous positions ([0, 1]), leaving 14 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 172.63.0.0/20, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 172.63.0.0/20 covers a range with 14 gaps (missing subnets like 172.63.2.0/24, 172.63.3.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.240.1. Fix: Split 172.63.0.0/20 into smaller, non-overlapping summaries that exactly cover only the 2 existing subnets (172.63.0.0/24, 172.63.1.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    172.44.1.0/24 [110/5] via 10.0.105.1, 00:01:49, GigabitEthernet0/1
O    173.80.166.192/27 [110/4] via 10.0.147.1, 00:01:35, GigabitEthernet0/0
S    172.44.0.0/21 [1/0] via 192.168.235.1
O    172.44.6.0/24 [110/3] via 10.0.172.1, 00:03:21, GigabitEthernet0/1
C    192.168.143.0/24 is directly connected, GigabitEthernet0/0
O    124.230.152.160/27 [110/5] via 10.0.3.1, 00:04:40, GigabitEthernet0/0
O    69.190.207.176/28 [110/2] via 10.0.46.1, 00:02:34, GigabitEthernet0/0

Question: Identify all potential issues in this routing table and classify them by severity.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.44.0.0/21 (S, via 192.168.235.1).
2. Observation: Only 2 specific routes exist within this summary: 172.44.1.0/24, 172.44.6.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 6 missing subnets between them (gaps at subnets [0, 2, 3, 4, 5]...).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.235.1 and potentially black-holed.
5. Impact: Traffic to any of the 6 gap subnets (e.g., 172.44.0.0/24, 172.44.2.0/24) will follow the summary route to 192.168.235.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 172.44.0.0/21 are at non-contiguous positions ([1, 6]), leaving 6 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 172.44.0.0/21, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 172.44.0.0/21 covers a range with 6 gaps (missing subnets like 172.44.0.0/24, 172.44.2.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.235.1. Fix: Split 172.44.0.0/21 into smaller, non-overlapping summaries that exactly cover only the 2 existing subnets (172.44.1.0/24, 172.44.6.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    172.225.7.0/24 [110/3] via 10.0.239.1, 00:05:56, GigabitEthernet0/1
S    172.225.0.0/21 [1/0] via 192.168.222.1
O    126.95.25.252/30 [110/4] via 10.0.209.1, 00:02:36, GigabitEthernet0/0
O    175.31.135.168/29 [110/3] via 10.0.155.1, 00:05:54, GigabitEthernet0/0
O    172.225.6.0/24 [110/2] via 10.0.236.1, 00:04:32, GigabitEthernet0/1
O    172.225.5.0/24 [110/4] via 10.0.115.1, 00:04:12, GigabitEthernet0/1
C    192.168.81.0/24 is directly connected, GigabitEthernet0/0

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.225.0.0/21 (S, via 192.168.222.1).
2. Observation: Only 3 specific routes exist within this summary: 172.225.5.0/24, 172.225.6.0/24, 172.225.7.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 5 missing subnets between them (gaps at subnets [0, 1, 2, 3, 4]).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.222.1 and potentially black-holed.
5. Impact: Traffic to any of the 5 gap subnets (e.g., 172.225.0.0/24, 172.225.1.0/24) will follow the summary route to 192.168.222.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 172.225.0.0/21 are at non-contiguous positions ([5, 6, 7]), leaving 5 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 172.225.0.0/21, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 172.225.0.0/21 covers a range with 5 gaps (missing subnets like 172.225.0.0/24, 172.225.1.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.222.1. Fix: Split 172.225.0.0/21 into smaller, non-overlapping summaries that exactly cover only the 3 existing subnets (172.225.5.0/24, 172.225.6.0/24, 172.225.7.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
S    172.7.0.0/20 [1/0] via 192.168.71.1
O    133.4.52.144/28 [110/3] via 10.0.54.1, 00:02:58, GigabitEthernet0/0
C    192.168.41.0/24 is directly connected, GigabitEthernet0/0
O    172.7.9.0/24 [110/5] via 10.0.117.1, 00:05:46, GigabitEthernet0/1
O    45.223.128.0/17 [110/4] via 10.0.24.1, 00:02:36, GigabitEthernet0/0
O    152.200.32.0/21 [110/4] via 10.0.40.1, 00:03:18, GigabitEthernet0/0
O    172.7.0.0/24 [110/3] via 10.0.243.1, 00:02:30, GigabitEthernet0/1

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.7.0.0/20 (S, via 192.168.71.1).
2. Observation: Only 2 specific routes exist within this summary: 172.7.0.0/24, 172.7.9.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 14 missing subnets between them (gaps at subnets [1, 2, 3, 4, 5]...).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.71.1 and potentially black-holed.
5. Impact: Traffic to any of the 14 gap subnets (e.g., 172.7.1.0/24, 172.7.2.0/24) will follow the summary route to 192.168.71.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 172.7.0.0/20 are at non-contiguous positions ([0, 9]), leaving 14 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 172.7.0.0/20, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 172.7.0.0/20 covers a range with 14 gaps (missing subnets like 172.7.1.0/24, 172.7.2.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.71.1. Fix: Split 172.7.0.0/20 into smaller, non-overlapping summaries that exactly cover only the 2 existing subnets (172.7.0.0/24, 172.7.9.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    10.39.2.0/24 [110/3] via 10.0.151.1, 00:02:42, GigabitEthernet0/1
O    10.39.3.0/24 [110/3] via 10.0.149.1, 00:04:21, GigabitEthernet0/1
O    200.201.225.0/24 [110/3] via 10.0.195.1, 00:04:48, GigabitEthernet0/0
C    192.168.91.0/24 is directly connected, GigabitEthernet0/0
O*IA 10.39.0.0/22 [110/2] via 192.168.11.1, 00:05:21, GigabitEthernet0/0
O    181.200.124.0/22 [110/2] via 10.0.18.1, 00:03:16, GigabitEthernet0/0
O    10.39.0.0/24 [110/4] via 10.0.81.1, 00:01:40, GigabitEthernet0/1

Question: Does this routing table contain any routing blackholes?

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 10.39.0.0/22 (O*IA, via 192.168.11.1).
2. Observation: Only 3 specific routes exist within this summary: 10.39.0.0/24, 10.39.2.0/24, 10.39.3.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 1 missing subnets between them (gaps at subnets [1]).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.11.1 and potentially black-holed.
5. Impact: Traffic to any of the 1 gap subnets (e.g., 10.39.1.0/24) will follow the summary route to 192.168.11.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 10.39.0.0/22 are at non-contiguous positions ([0, 2, 3]), leaving 1 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 10.39.0.0/22, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 10.39.0.0/22 covers a range with 1 gaps (missing subnets like 10.39.1.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.11.1. Fix: Split 10.39.0.0/22 into smaller, non-overlapping summaries that exactly cover only the 3 existing subnets (10.39.0.0/24, 10.39.2.0/24, 10.39.3.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    36.248.38.0/26 [110/5] via 10.0.193.1, 00:02:49, GigabitEthernet0/0
O    159.79.251.240/29 [110/2] via 10.0.39.1, 00:04:53, GigabitEthernet0/0
S    172.198.0.0/21 [1/0] via 192.168.49.1
C    192.168.50.0/24 is directly connected, GigabitEthernet0/0
O    172.198.0.0/24 [110/2] via 10.0.212.1, 00:03:11, GigabitEthernet0/1
O    172.198.7.0/24 [110/3] via 10.0.210.1, 00:01:52, GigabitEthernet0/1

Question: Does this routing table contain any routing blackholes?

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.198.0.0/21 (S, via 192.168.49.1).
2. Observation: Only 2 specific routes exist within this summary: 172.198.0.0/24, 172.198.7.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 6 missing subnets between them (gaps at subnets [1, 2, 3, 4, 5]...).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.49.1 and potentially black-holed.
5. Impact: Traffic to any of the 6 gap subnets (e.g., 172.198.1.0/24, 172.198.2.0/24) will follow the summary route to 192.168.49.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 172.198.0.0/21 are at non-contiguous positions ([0, 7]), leaving 6 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 172.198.0.0/21, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 172.198.0.0/21 covers a range with 6 gaps (missing subnets like 172.198.1.0/24, 172.198.2.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.49.1. Fix: Split 172.198.0.0/21 into smaller, non-overlapping summaries that exactly cover only the 2 existing subnets (172.198.0.0/24, 172.198.7.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
O    81.168.32.0/19 [110/3] via 10.0.80.1, 00:01:54, GigabitEthernet0/0
O    55.170.146.160/27 [110/5] via 10.0.193.1, 00:05:40, GigabitEthernet0/0
O*IA 10.198.0.0/21 [110/2] via 192.168.153.1, 00:03:46, GigabitEthernet0/0
O    10.198.4.0/24 [110/3] via 10.0.124.1, 00:05:56, GigabitEthernet0/1
C    192.168.147.0/24 is directly connected, GigabitEthernet0/0
O    10.198.0.0/24 [110/2] via 10.0.72.1, 00:03:55, GigabitEthernet0/1

Question: Analyze this routing table for traffic blackholing risks.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 10.198.0.0/21 (O*IA, via 192.168.153.1).
2. Observation: Only 2 specific routes exist within this summary: 10.198.0.0/24, 10.198.4.0/24.
3. Observation: These specific routes are NOT contiguous within the summary range. There are 6 missing subnets between them (gaps at subnets [1, 2, 3, 5, 6]...).
4. Analysis: A proper summary route should cover a contiguous block of subnets. When subnets are scattered with gaps, the summary still advertises the entire range, causing traffic to the gap subnets to be forwarded to 192.168.153.1 and potentially black-holed.
5. Impact: Traffic to any of the 6 gap subnets (e.g., 10.198.1.0/24, 10.198.2.0/24) will follow the summary route to 192.168.153.1 instead of being dropped locally or routed correctly. This creates silent packet loss for destinations that don't exist.
6. Detection: The specific routes within 10.198.0.0/21 are at non-contiguous positions ([0, 4]), leaving 6 gaps. A valid summary requires contiguous coverage.
7. Recommendation: Either (a) add routes for all missing subnets within 10.198.0.0/21, (b) split the summary into multiple smaller summaries that exactly cover only the existing subnets, or (c) use explicit null0 routes for the gap subnets to prevent blackholing.
</reasoning>
<answer>
CRITICAL: Discontiguous summary detected. 10.198.0.0/21 covers a range with 6 gaps (missing subnets like 10.198.1.0/24, 10.198.2.0/24). Traffic to non-existent gap subnets will be black-holed at 192.168.153.1. Fix: Split 10.198.0.0/21 into smaller, non-overlapping summaries that exactly cover only the 2 existing subnets (10.198.0.0/24, 10.198.4.0/24), or add explicit routes/null0 for all gaps.
</answer>


[System] You are a network routing expert. Analyze the routing table, detect issues, and provide step-by-step reasoning. Use the format: <reasoning>...step-by-step analysis...</reasoning><answer>...concise answer...</answer>

[User]
Routing table:
C    192.168.17.0/24 is directly connected, GigabitEthernet0/0
O    157.211.0.0/17 [110/2] via 10.0.77.1, 00:02:15, GigabitEthernet0/0
O*IA 172.177.0.0/23 [110/2] via 192.168.10.1, 00:01:36, GigabitEthernet0/0
O    172.177.0.0/24 [110/5] via 10.0.36.2, 00:02:31, GigabitEthernet0/0
O    172.177.1.0/24 [110/5] via 10.0.253.1, 00:03:53, GigabitEthernet0/1
O    170.77.38.0/25 [110/3] via 10.0.139.1, 00:01:56, GigabitEthernet0/0
O    199.66.216.240/28 [110/5] via 10.0.110.1, 00:04:38, GigabitEthernet0/0
O    157.150.96.0/20 [110/4] via 10.0.102.1, 00:02:13, GigabitEthernet0/0

Question: Identify all potential issues in this routing table and classify them by severity.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.177.0.0/23 (O*IA, via 192.168.10.1) covering 2 /24 subnets.
2. Observation: Subnets 172.177.1.0/24 are explicitly routed via OSPF. However, 172.177.0.0/24 is also present but routed via a DIFFERENT next-hop (not 192.168.10.1).
3. Analysis: The summary route 172.177.0.0/23 claims to cover 172.177.0.0/24, but 172.177.0.0/24 has its own specific route. Due to longest-prefix-match, the /24 route to 172.177.0.0/24 will override the summary. This is technically correct but indicates poor summarization design — the summary and specific routes are not aligned.
4. Impact: Traffic to 172.177.0.0/24 takes a different path than traffic to adjacent subnets in the same summary range. This creates asymmetric routing within what should be a unified address block, complicating troubleshooting and potentially breaking stateful services.
5. Detection: 172.177.0.0/24 is within 172.177.0.0/23 but has a separate, non-summary next-hop, creating a "hole" in the summary's unified forwarding behavior.
6. Recommendation: Either remove the specific route for 172.177.0.0/24 and let it follow the summary, or split the summary into two non-overlapping summaries that exclude 172.177.0.0/24. Ensure all subnets within a summary range follow consistent forwarding paths.
</reasoning>
<answer>
WARNING: Hole in summary detected. 172.177.0.0/23 (O*IA) covers 172.177.0.0/24, but 172.177.0.0/24 has a separate specific route via a different next-hop. This creates inconsistent forwarding within the summary range. Fix: Align 172.177.0.0/24 with the summary next-hop 192.168.10.1, or restructure summaries to exclude 172.177.0.0/24. Ensure all subnets within a summary follow the same path.
</answer>