[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    192.168.189.0/24 is directly connected, GigabitEthernet0/0
O    55.130.14.0/24 [110/2] via 10.0.220.1, 00:01:47, GigabitEthernet0/0
O    172.214.1.0/24 [110/4] via 10.0.224.1, 00:02:13, GigabitEthernet0/1
O    21.65.142.64/26 [110/5] via 10.0.247.1, 00:02:30, GigabitEthernet0/0
O*IA 172.214.0.0/23 [110/2] via 192.168.245.1, 00:02:46, GigabitEthernet0/0
O    172.214.0.0/24 [110/4] via 10.0.58.2, 00:05:13, 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 172.214.0.0/23 (O*IA, via 192.168.245.1) covering 2 /24 subnets.
2. Observation: Subnets 172.214.1.0/24 are explicitly routed via OSPF. However, 172.214.0.0/24 is also present but routed via a DIFFERENT next-hop (not 192.168.245.1).
3. Analysis: The summary route 172.214.0.0/23 claims to cover 172.214.0.0/24, but 172.214.0.0/24 has its own specific route. Due to longest-prefix-match, the /24 route to 172.214.0.0/24 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 172.214.0.0/24 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: 172.214.0.0/24 is within 172.214.0.0/23 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 172.214.0.0/24 and let it follow the summary, or split the summary into two non-overlapping summaries that exclude 172.214.0.0/24. Ensure all subnets within a summary range follow consistent forwarding paths.
</reasoning>
<answer>
WARNING: Hole in summary detected. 172.214.0.0/23 (O*IA) covers 172.214.0.0/24, but 172.214.0.0/24 has a separate specific route via a different next-hop. This creates inconsistent forwarding within the summary range. Fix: Align 172.214.0.0/24 with the summary next-hop 192.168.245.1, or restructure summaries to exclude 172.214.0.0/24. Ensure all subnets within a summary follow the same path.
</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 10.59.0.0/23 [110/2] via 192.168.138.1, 00:02:27, GigabitEthernet0/0
O    3.108.203.80/28 [110/3] via 10.0.181.1, 00:01:37, GigabitEthernet0/0
C    192.168.221.0/24 is directly connected, GigabitEthernet0/0
O    197.115.195.224/29 [110/5] via 10.0.31.1, 00:01:55, GigabitEthernet0/0
O    10.59.1.0/24 [110/3] via 10.0.159.1, 00:05:35, GigabitEthernet0/1

Question: Does this routing table contain any routing blackholes?

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 10.59.0.0/23 (O*IA, via 192.168.138.1).
2. Observation: Within this summary, subnets 10.59.1.0/24 (and -1 more) have explicit OSPF routes. However, 10.59.0.0/24 has NO specific route.
3. Analysis: Because 10.59.0.0/24 has no explicit route, traffic to it will follow the summary route 10.59.0.0/23 to 192.168.138.1. If 192.168.138.1 does not have a route for 10.59.0.0/24 or drops the traffic, this creates a blackhole for that specific subnet.
4. Impact: The missing subnet 10.59.0.0/24 appears to be "covered" by the summary but is actually unreachable. This is a silent failure — the summary makes it look like the subnet should work, but traffic is lost.
5. Detection: Prefix coverage analysis of 10.59.0.0/23 reveals that 10.59.0.0/24 is NOT explicitly routed, despite being within the summary range. No more-specific route exists to override the summary.
6. Recommendation: Add an explicit route for 10.59.0.0/24 via the correct next-hop, or if the subnet is intentionally unused, configure a null0 route for 10.59.0.0/24 to explicitly discard traffic rather than silently black-holing it.
</reasoning>
<answer>
CRITICAL: Hole in summary detected. 10.59.0.0/23 covers 10.59.0.0/24, but 10.59.0.0/24 has no specific route. Traffic to 10.59.0.0/24 will follow the summary to 192.168.138.1 and be black-holed. Fix: Add an explicit route for 10.59.0.0/24 via the correct next-hop, or configure a null0 route if the subnet is intentionally unused. Do not rely on summary routes for subnets that are not actually reachable.
</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    172.14.1.0/24 [110/3] via 10.0.162.1, 00:04:14, GigabitEthernet0/1
O    172.14.2.0/24 [110/2] via 10.0.220.1, 00:04:22, GigabitEthernet0/1
O    48.231.92.0/23 [110/4] via 10.0.16.1, 00:01:19, GigabitEthernet0/0
O*IA 172.14.0.0/22 [110/2] via 192.168.35.1, 00:03:43, GigabitEthernet0/0
O    75.240.242.36/30 [110/5] via 10.0.216.1, 00:05:33, GigabitEthernet0/0
O    187.26.0.0/16 [110/5] via 10.0.181.1, 00:04:55, GigabitEthernet0/0
O    172.14.0.0/24 [110/3] via 10.0.165.1, 00:01:49, GigabitEthernet0/1
O    172.14.3.0/24 [110/4] via 10.0.230.2, 00:03:46, GigabitEthernet0/0
C    192.168.13.0/24 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 a summary route 172.14.0.0/22 (O*IA, via 192.168.35.1) covering 4 /24 subnets.
2. Observation: Subnets 172.14.0.0/24, 172.14.1.0/24, 172.14.2.0/24 are explicitly routed via OSPF. However, 172.14.3.0/24 is also present but routed via a DIFFERENT next-hop (not 192.168.35.1).
3. Analysis: The summary route 172.14.0.0/22 claims to cover 172.14.3.0/24, but 172.14.3.0/24 has its own specific route. Due to longest-prefix-match, the /24 route to 172.14.3.0/24 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 172.14.3.0/24 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: 172.14.3.0/24 is within 172.14.0.0/22 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 172.14.3.0/24 and let it follow the summary, or split the summary into two non-overlapping summaries that exclude 172.14.3.0/24. Ensure all subnets within a summary range follow consistent forwarding paths.
</reasoning>
<answer>
WARNING: Hole in summary detected. 172.14.0.0/22 (O*IA) covers 172.14.3.0/24, but 172.14.3.0/24 has a separate specific route via a different next-hop. This creates inconsistent forwarding within the summary range. Fix: Align 172.14.3.0/24 with the summary next-hop 192.168.35.1, or restructure summaries to exclude 172.14.3.0/24. Ensure all subnets within a summary follow the same path.
</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    172.176.3.0/24 [110/2] via 10.0.144.1, 00:01:55, GigabitEthernet0/1
O    176.222.66.128/25 [110/3] via 10.0.32.1, 00:04:30, GigabitEthernet0/0
S    172.176.0.0/22 [1/0] via 192.168.129.1
O    172.176.1.0/24 [110/3] via 10.0.170.1, 00:02:26, GigabitEthernet0/1
O    209.186.0.0/16 [110/5] via 10.0.55.1, 00:02:52, GigabitEthernet0/0
C    192.168.84.0/24 is directly connected, GigabitEthernet0/0
O    172.176.0.0/24 [110/4] via 10.0.146.1, 00:05:16, GigabitEthernet0/1

Question: Does this routing table contain any routing blackholes?

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.176.0.0/22 (S, via 192.168.129.1).
2. Observation: Within this summary, subnets 172.176.0.0/24, 172.176.1.0/24 (and 1 more) have explicit OSPF routes. However, 172.176.2.0/24 has NO specific route.
3. Analysis: Because 172.176.2.0/24 has no explicit route, traffic to it will follow the summary route 172.176.0.0/22 to 192.168.129.1. If 192.168.129.1 does not have a route for 172.176.2.0/24 or drops the traffic, this creates a blackhole for that specific subnet.
4. Impact: The missing subnet 172.176.2.0/24 appears to be "covered" by the summary but is actually unreachable. This is a silent failure — the summary makes it look like the subnet should work, but traffic is lost.
5. Detection: Prefix coverage analysis of 172.176.0.0/22 reveals that 172.176.2.0/24 is NOT explicitly routed, despite being within the summary range. No more-specific route exists to override the summary.
6. Recommendation: Add an explicit route for 172.176.2.0/24 via the correct next-hop, or if the subnet is intentionally unused, configure a null0 route for 172.176.2.0/24 to explicitly discard traffic rather than silently black-holing it.
</reasoning>
<answer>
CRITICAL: Hole in summary detected. 172.176.0.0/22 covers 172.176.2.0/24, but 172.176.2.0/24 has no specific route. Traffic to 172.176.2.0/24 will follow the summary to 192.168.129.1 and be black-holed. Fix: Add an explicit route for 172.176.2.0/24 via the correct next-hop, or configure a null0 route if the subnet is intentionally unused. Do not rely on summary routes for subnets that are not actually reachable.
</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    192.168.150.0/24 is directly connected, GigabitEthernet0/0
O    68.227.128.0/18 [110/3] via 10.0.232.1, 00:03:28, GigabitEthernet0/0
O*IA 172.17.0.0/23 [110/2] via 192.168.142.1, 00:03:41, GigabitEthernet0/0
O    162.218.116.0/22 [110/3] via 10.0.229.1, 00:04:17, GigabitEthernet0/0
O    172.17.0.0/24 [110/5] via 10.0.67.2, 00:03:20, GigabitEthernet0/0
O    62.41.184.0/21 [110/4] via 10.0.254.1, 00:04:55, GigabitEthernet0/0
O    172.17.1.0/24 [110/3] via 10.0.159.1, 00:02:13, GigabitEthernet0/1

Question: Analyze this routing table for traffic blackholing risks.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.17.0.0/23 (O*IA, via 192.168.142.1) covering 2 /24 subnets.
2. Observation: Subnets 172.17.1.0/24 are explicitly routed via OSPF. However, 172.17.0.0/24 is also present but routed via a DIFFERENT next-hop (not 192.168.142.1).
3. Analysis: The summary route 172.17.0.0/23 claims to cover 172.17.0.0/24, but 172.17.0.0/24 has its own specific route. Due to longest-prefix-match, the /24 route to 172.17.0.0/24 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 172.17.0.0/24 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: 172.17.0.0/24 is within 172.17.0.0/23 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 172.17.0.0/24 and let it follow the summary, or split the summary into two non-overlapping summaries that exclude 172.17.0.0/24. Ensure all subnets within a summary range follow consistent forwarding paths.
</reasoning>
<answer>
WARNING: Hole in summary detected. 172.17.0.0/23 (O*IA) covers 172.17.0.0/24, but 172.17.0.0/24 has a separate specific route via a different next-hop. This creates inconsistent forwarding within the summary range. Fix: Align 172.17.0.0/24 with the summary next-hop 192.168.142.1, or restructure summaries to exclude 172.17.0.0/24. Ensure all subnets within a summary follow the same path.
</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    172.144.64.0/18 [110/4] via 10.0.113.1, 00:05:31, GigabitEthernet0/0
C    192.168.72.0/24 is directly connected, GigabitEthernet0/0
O    3.141.46.0/23 [110/5] via 10.0.4.1, 00:01:50, GigabitEthernet0/0
O    172.50.1.0/24 [110/5] via 10.0.114.2, 00:04:23, GigabitEthernet0/0
O    178.103.128.0/19 [110/3] via 10.0.63.1, 00:03:57, GigabitEthernet0/0
O    77.175.223.64/26 [110/4] via 10.0.236.1, 00:02:54, GigabitEthernet0/0
O*IA 172.50.0.0/22 [110/2] via 192.168.124.1, 00:01:15, GigabitEthernet0/0
O    172.50.0.0/24 [110/3] via 10.0.241.1, 00:04:54, GigabitEthernet0/1
O    172.50.3.0/24 [110/2] via 10.0.31.1, 00:03:51, GigabitEthernet0/1
O    172.50.2.0/24 [110/5] via 10.0.197.1, 00:02:45, GigabitEthernet0/1

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.50.0.0/22 (O*IA, via 192.168.124.1) covering 4 /24 subnets.
2. Observation: Subnets 172.50.0.0/24, 172.50.2.0/24, 172.50.3.0/24 are explicitly routed via OSPF. However, 172.50.1.0/24 is also present but routed via a DIFFERENT next-hop (not 192.168.124.1).
3. Analysis: The summary route 172.50.0.0/22 claims to cover 172.50.1.0/24, but 172.50.1.0/24 has its own specific route. Due to longest-prefix-match, the /24 route to 172.50.1.0/24 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 172.50.1.0/24 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: 172.50.1.0/24 is within 172.50.0.0/22 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 172.50.1.0/24 and let it follow the summary, or split the summary into two non-overlapping summaries that exclude 172.50.1.0/24. Ensure all subnets within a summary range follow consistent forwarding paths.
</reasoning>
<answer>
WARNING: Hole in summary detected. 172.50.0.0/22 (O*IA) covers 172.50.1.0/24, but 172.50.1.0/24 has a separate specific route via a different next-hop. This creates inconsistent forwarding within the summary range. Fix: Align 172.50.1.0/24 with the summary next-hop 192.168.124.1, or restructure summaries to exclude 172.50.1.0/24. Ensure all subnets within a summary follow the same path.
</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    22.222.237.0/27 [110/3] via 10.0.73.1, 00:05:56, GigabitEthernet0/0
O    97.53.252.0/22 [110/3] via 10.0.62.1, 00:02:32, GigabitEthernet0/0
O    172.113.0.0/24 [110/5] via 10.0.215.1, 00:03:59, GigabitEthernet0/1
O    172.113.2.0/24 [110/3] via 10.0.10.1, 00:03:41, GigabitEthernet0/1
O*IA 172.113.0.0/22 [110/2] via 192.168.85.1, 00:03:59, GigabitEthernet0/0
O    172.113.3.0/24 [110/5] via 10.0.199.1, 00:04:51, 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 172.113.0.0/22 (O*IA, via 192.168.85.1).
2. Observation: Within this summary, subnets 172.113.0.0/24, 172.113.2.0/24 (and 1 more) have explicit OSPF routes. However, 172.113.1.0/24 has NO specific route.
3. Analysis: Because 172.113.1.0/24 has no explicit route, traffic to it will follow the summary route 172.113.0.0/22 to 192.168.85.1. If 192.168.85.1 does not have a route for 172.113.1.0/24 or drops the traffic, this creates a blackhole for that specific subnet.
4. Impact: The missing subnet 172.113.1.0/24 appears to be "covered" by the summary but is actually unreachable. This is a silent failure — the summary makes it look like the subnet should work, but traffic is lost.
5. Detection: Prefix coverage analysis of 172.113.0.0/22 reveals that 172.113.1.0/24 is NOT explicitly routed, despite being within the summary range. No more-specific route exists to override the summary.
6. Recommendation: Add an explicit route for 172.113.1.0/24 via the correct next-hop, or if the subnet is intentionally unused, configure a null0 route for 172.113.1.0/24 to explicitly discard traffic rather than silently black-holing it.
</reasoning>
<answer>
CRITICAL: Hole in summary detected. 172.113.0.0/22 covers 172.113.1.0/24, but 172.113.1.0/24 has no specific route. Traffic to 172.113.1.0/24 will follow the summary to 192.168.85.1 and be black-holed. Fix: Add an explicit route for 172.113.1.0/24 via the correct next-hop, or configure a null0 route if the subnet is intentionally unused. Do not rely on summary routes for subnets that are not actually reachable.
</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    10.178.1.0/24 [110/3] via 10.0.28.1, 00:01:27, GigabitEthernet0/1
O    151.188.68.0/22 [110/2] via 10.0.163.1, 00:03:12, GigabitEthernet0/0
C    192.168.8.0/24 is directly connected, GigabitEthernet0/0
O    144.218.192.224/29 [110/5] via 10.0.155.1, 00:04:47, GigabitEthernet0/0
O    10.178.0.0/24 [110/4] via 10.0.229.2, 00:03:50, GigabitEthernet0/0
O*IA 10.178.0.0/23 [110/2] via 192.168.134.1, 00:05:49, GigabitEthernet0/0

Question: Does this routing table contain any routing blackholes?

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 10.178.0.0/23 (O*IA, via 192.168.134.1) covering 2 /24 subnets.
2. Observation: Subnets 10.178.1.0/24 are explicitly routed via OSPF. However, 10.178.0.0/24 is also present but routed via a DIFFERENT next-hop (not 192.168.134.1).
3. Analysis: The summary route 10.178.0.0/23 claims to cover 10.178.0.0/24, but 10.178.0.0/24 has its own specific route. Due to longest-prefix-match, the /24 route to 10.178.0.0/24 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 10.178.0.0/24 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: 10.178.0.0/24 is within 10.178.0.0/23 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 10.178.0.0/24 and let it follow the summary, or split the summary into two non-overlapping summaries that exclude 10.178.0.0/24. Ensure all subnets within a summary range follow consistent forwarding paths.
</reasoning>
<answer>
WARNING: Hole in summary detected. 10.178.0.0/23 (O*IA) covers 10.178.0.0/24, but 10.178.0.0/24 has a separate specific route via a different next-hop. This creates inconsistent forwarding within the summary range. Fix: Align 10.178.0.0/24 with the summary next-hop 192.168.134.1, or restructure summaries to exclude 10.178.0.0/24. Ensure all subnets within a summary follow the same path.
</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    172.151.0.0/24 [110/5] via 10.0.90.1, 00:04:32, GigabitEthernet0/1
O    31.134.32.0/21 [110/4] via 10.0.224.1, 00:03:12, GigabitEthernet0/0
O    172.151.3.0/24 [110/3] via 10.0.254.1, 00:01:11, GigabitEthernet0/1
O    172.151.1.0/24 [110/5] via 10.0.128.2, 00:02:17, GigabitEthernet0/0
O    172.151.2.0/24 [110/2] via 10.0.8.1, 00:05:39, GigabitEthernet0/1
C    192.168.78.0/24 is directly connected, GigabitEthernet0/0
O    184.191.160.0/19 [110/5] via 10.0.247.1, 00:01:18, GigabitEthernet0/0
S    172.151.0.0/22 [1/0] via 192.168.205.1

Question: Does this routing table contain any routing blackholes?

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.151.0.0/22 (S, via 192.168.205.1) covering 4 /24 subnets.
2. Observation: Subnets 172.151.0.0/24, 172.151.2.0/24, 172.151.3.0/24 are explicitly routed via OSPF. However, 172.151.1.0/24 is also present but routed via a DIFFERENT next-hop (not 192.168.205.1).
3. Analysis: The summary route 172.151.0.0/22 claims to cover 172.151.1.0/24, but 172.151.1.0/24 has its own specific route. Due to longest-prefix-match, the /24 route to 172.151.1.0/24 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 172.151.1.0/24 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: 172.151.1.0/24 is within 172.151.0.0/22 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 172.151.1.0/24 and let it follow the summary, or split the summary into two non-overlapping summaries that exclude 172.151.1.0/24. Ensure all subnets within a summary range follow consistent forwarding paths.
</reasoning>
<answer>
WARNING: Hole in summary detected. 172.151.0.0/22 (S) covers 172.151.1.0/24, but 172.151.1.0/24 has a separate specific route via a different next-hop. This creates inconsistent forwarding within the summary range. Fix: Align 172.151.1.0/24 with the summary next-hop 192.168.205.1, or restructure summaries to exclude 172.151.1.0/24. Ensure all subnets within a summary follow the same path.
</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    107.13.0.0/16 [110/2] via 10.0.214.1, 00:03:58, GigabitEthernet0/0
C    192.168.244.0/24 is directly connected, GigabitEthernet0/0
O    149.214.0.0/18 [110/5] via 10.0.127.1, 00:02:53, GigabitEthernet0/0
O*IA 10.87.0.0/23 [110/2] via 192.168.157.1, 00:02:36, GigabitEthernet0/0
O    10.87.0.0/24 [110/4] via 10.0.216.1, 00:04:48, GigabitEthernet0/1
O    168.16.48.0/21 [110/5] via 10.0.31.1, 00:01:24, GigabitEthernet0/0
O    10.87.1.0/24 [110/4] via 10.0.229.2, 00:02:55, GigabitEthernet0/0

Question: Analyze this routing table for traffic blackholing risks.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 10.87.0.0/23 (O*IA, via 192.168.157.1) covering 2 /24 subnets.
2. Observation: Subnets 10.87.0.0/24 are explicitly routed via OSPF. However, 10.87.1.0/24 is also present but routed via a DIFFERENT next-hop (not 192.168.157.1).
3. Analysis: The summary route 10.87.0.0/23 claims to cover 10.87.1.0/24, but 10.87.1.0/24 has its own specific route. Due to longest-prefix-match, the /24 route to 10.87.1.0/24 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 10.87.1.0/24 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: 10.87.1.0/24 is within 10.87.0.0/23 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 10.87.1.0/24 and let it follow the summary, or split the summary into two non-overlapping summaries that exclude 10.87.1.0/24. Ensure all subnets within a summary range follow consistent forwarding paths.
</reasoning>
<answer>
WARNING: Hole in summary detected. 10.87.0.0/23 (O*IA) covers 10.87.1.0/24, but 10.87.1.0/24 has a separate specific route via a different next-hop. This creates inconsistent forwarding within the summary range. Fix: Align 10.87.1.0/24 with the summary next-hop 192.168.157.1, or restructure summaries to exclude 10.87.1.0/24. Ensure all subnets within a summary follow the same path.
</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    10.15.1.0/24 [110/2] via 10.0.181.1, 00:02:13, GigabitEthernet0/1
C    192.168.1.0/24 is directly connected, GigabitEthernet0/0
O    10.15.0.0/24 [110/2] via 10.0.126.1, 00:02:31, GigabitEthernet0/1
O    66.214.179.100/30 [110/5] via 10.0.29.1, 00:05:48, GigabitEthernet0/0
O    21.34.0.0/17 [110/3] via 10.0.223.1, 00:04:33, GigabitEthernet0/0
O*IA 10.15.0.0/22 [110/2] via 192.168.249.1, 00:05:45, GigabitEthernet0/0
O    10.15.2.0/24 [110/4] via 10.0.28.1, 00:02:35, GigabitEthernet0/1

Question: Analyze this routing table for traffic blackholing risks.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 10.15.0.0/22 (O*IA, via 192.168.249.1).
2. Observation: Within this summary, subnets 10.15.0.0/24, 10.15.1.0/24 (and 1 more) have explicit OSPF routes. However, 10.15.3.0/24 has NO specific route.
3. Analysis: Because 10.15.3.0/24 has no explicit route, traffic to it will follow the summary route 10.15.0.0/22 to 192.168.249.1. If 192.168.249.1 does not have a route for 10.15.3.0/24 or drops the traffic, this creates a blackhole for that specific subnet.
4. Impact: The missing subnet 10.15.3.0/24 appears to be "covered" by the summary but is actually unreachable. This is a silent failure — the summary makes it look like the subnet should work, but traffic is lost.
5. Detection: Prefix coverage analysis of 10.15.0.0/22 reveals that 10.15.3.0/24 is NOT explicitly routed, despite being within the summary range. No more-specific route exists to override the summary.
6. Recommendation: Add an explicit route for 10.15.3.0/24 via the correct next-hop, or if the subnet is intentionally unused, configure a null0 route for 10.15.3.0/24 to explicitly discard traffic rather than silently black-holing it.
</reasoning>
<answer>
CRITICAL: Hole in summary detected. 10.15.0.0/22 covers 10.15.3.0/24, but 10.15.3.0/24 has no specific route. Traffic to 10.15.3.0/24 will follow the summary to 192.168.249.1 and be black-holed. Fix: Add an explicit route for 10.15.3.0/24 via the correct next-hop, or configure a null0 route if the subnet is intentionally unused. Do not rely on summary routes for subnets that are not actually reachable.
</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    172.174.1.0/24 [110/5] via 10.0.75.1, 00:03:58, GigabitEthernet0/1
O    70.54.80.0/24 [110/3] via 10.0.175.1, 00:04:26, GigabitEthernet0/0
O    172.174.3.0/24 [110/5] via 10.0.134.2, 00:03:39, GigabitEthernet0/0
S    172.174.0.0/22 [1/0] via 192.168.154.1
C    192.168.202.0/24 is directly connected, GigabitEthernet0/0
O    190.57.156.0/24 [110/4] via 10.0.69.1, 00:02:26, GigabitEthernet0/0
O    172.174.0.0/24 [110/5] via 10.0.147.1, 00:02:36, GigabitEthernet0/1
O    61.234.128.0/18 [110/4] via 10.0.197.1, 00:05:33, GigabitEthernet0/0
O    195.216.123.56/29 [110/5] via 10.0.197.1, 00:05:30, GigabitEthernet0/0
O    172.174.2.0/24 [110/4] via 10.0.249.1, 00:02:16, GigabitEthernet0/1

Question: Analyze this routing table for traffic blackholing risks.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.174.0.0/22 (S, via 192.168.154.1) covering 4 /24 subnets.
2. Observation: Subnets 172.174.0.0/24, 172.174.1.0/24, 172.174.2.0/24 are explicitly routed via OSPF. However, 172.174.3.0/24 is also present but routed via a DIFFERENT next-hop (not 192.168.154.1).
3. Analysis: The summary route 172.174.0.0/22 claims to cover 172.174.3.0/24, but 172.174.3.0/24 has its own specific route. Due to longest-prefix-match, the /24 route to 172.174.3.0/24 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 172.174.3.0/24 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: 172.174.3.0/24 is within 172.174.0.0/22 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 172.174.3.0/24 and let it follow the summary, or split the summary into two non-overlapping summaries that exclude 172.174.3.0/24. Ensure all subnets within a summary range follow consistent forwarding paths.
</reasoning>
<answer>
WARNING: Hole in summary detected. 172.174.0.0/22 (S) covers 172.174.3.0/24, but 172.174.3.0/24 has a separate specific route via a different next-hop. This creates inconsistent forwarding within the summary range. Fix: Align 172.174.3.0/24 with the summary next-hop 192.168.154.1, or restructure summaries to exclude 172.174.3.0/24. Ensure all subnets within a summary follow the same path.
</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    10.137.3.0/24 [110/5] via 10.0.26.1, 00:01:39, GigabitEthernet0/1
O*IA 10.137.0.0/22 [110/2] via 192.168.234.1, 00:04:20, GigabitEthernet0/0
O    4.225.0.0/16 [110/3] via 10.0.192.1, 00:04:11, GigabitEthernet0/0
O    10.137.0.0/24 [110/2] via 10.0.247.2, 00:02:36, GigabitEthernet0/0
O    10.137.2.0/24 [110/5] via 10.0.213.1, 00:05:45, GigabitEthernet0/1
C    192.168.68.0/24 is directly connected, GigabitEthernet0/0
O    10.137.1.0/24 [110/3] via 10.0.160.1, 00:03:51, GigabitEthernet0/1
O    66.203.80.0/21 [110/4] via 10.0.182.1, 00:02:27, GigabitEthernet0/0

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 10.137.0.0/22 (O*IA, via 192.168.234.1) covering 4 /24 subnets.
2. Observation: Subnets 10.137.1.0/24, 10.137.2.0/24, 10.137.3.0/24 are explicitly routed via OSPF. However, 10.137.0.0/24 is also present but routed via a DIFFERENT next-hop (not 192.168.234.1).
3. Analysis: The summary route 10.137.0.0/22 claims to cover 10.137.0.0/24, but 10.137.0.0/24 has its own specific route. Due to longest-prefix-match, the /24 route to 10.137.0.0/24 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 10.137.0.0/24 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: 10.137.0.0/24 is within 10.137.0.0/22 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 10.137.0.0/24 and let it follow the summary, or split the summary into two non-overlapping summaries that exclude 10.137.0.0/24. Ensure all subnets within a summary range follow consistent forwarding paths.
</reasoning>
<answer>
WARNING: Hole in summary detected. 10.137.0.0/22 (O*IA) covers 10.137.0.0/24, but 10.137.0.0/24 has a separate specific route via a different next-hop. This creates inconsistent forwarding within the summary range. Fix: Align 10.137.0.0/24 with the summary next-hop 192.168.234.1, or restructure summaries to exclude 10.137.0.0/24. Ensure all subnets within a summary follow the same path.
</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    10.112.1.0/24 [110/2] via 10.0.54.1, 00:05:33, GigabitEthernet0/1
C    192.168.127.0/24 is directly connected, GigabitEthernet0/0
O    107.176.6.0/26 [110/4] via 10.0.194.1, 00:01:33, GigabitEthernet0/0
O    195.152.136.96/30 [110/3] via 10.0.233.1, 00:03:40, GigabitEthernet0/0
O    220.45.144.0/20 [110/3] via 10.0.22.1, 00:03:15, GigabitEthernet0/0
O    133.187.109.176/29 [110/2] via 10.0.121.1, 00:01:40, GigabitEthernet0/0
O    10.112.0.0/24 [110/3] via 10.0.201.2, 00:02:54, GigabitEthernet0/0
S    10.112.0.0/23 [1/0] via 192.168.14.1

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 10.112.0.0/23 (S, via 192.168.14.1) covering 2 /24 subnets.
2. Observation: Subnets 10.112.1.0/24 are explicitly routed via OSPF. However, 10.112.0.0/24 is also present but routed via a DIFFERENT next-hop (not 192.168.14.1).
3. Analysis: The summary route 10.112.0.0/23 claims to cover 10.112.0.0/24, but 10.112.0.0/24 has its own specific route. Due to longest-prefix-match, the /24 route to 10.112.0.0/24 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 10.112.0.0/24 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: 10.112.0.0/24 is within 10.112.0.0/23 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 10.112.0.0/24 and let it follow the summary, or split the summary into two non-overlapping summaries that exclude 10.112.0.0/24. Ensure all subnets within a summary range follow consistent forwarding paths.
</reasoning>
<answer>
WARNING: Hole in summary detected. 10.112.0.0/23 (S) covers 10.112.0.0/24, but 10.112.0.0/24 has a separate specific route via a different next-hop. This creates inconsistent forwarding within the summary range. Fix: Align 10.112.0.0/24 with the summary next-hop 192.168.14.1, or restructure summaries to exclude 10.112.0.0/24. Ensure all subnets within a summary follow the same path.
</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    172.242.0.0/24 [110/5] via 10.0.74.1, 00:05:15, GigabitEthernet0/1
C    192.168.65.0/24 is directly connected, GigabitEthernet0/0
O    172.242.2.0/24 [110/3] via 10.0.13.1, 00:04:55, GigabitEthernet0/1
S    172.242.0.0/22 [1/0] via 192.168.135.1
O    176.3.144.0/20 [110/2] via 10.0.121.1, 00:03:41, GigabitEthernet0/0
O    172.242.1.0/24 [110/3] via 10.0.108.2, 00:03:37, GigabitEthernet0/0
O    172.242.3.0/24 [110/3] via 10.0.35.1, 00:01:19, GigabitEthernet0/1
O    38.71.212.0/22 [110/5] via 10.0.94.1, 00:04:14, GigabitEthernet0/0

Question: Identify any summarization errors in this routing table.

[Assistant]
<reasoning>
1. Observation: The routing table contains a summary route 172.242.0.0/22 (S, via 192.168.135.1) covering 4 /24 subnets.
2. Observation: Subnets 172.242.0.0/24, 172.242.2.0/24, 172.242.3.0/24 are explicitly routed via OSPF. However, 172.242.1.0/24 is also present but routed via a DIFFERENT next-hop (not 192.168.135.1).
3. Analysis: The summary route 172.242.0.0/22 claims to cover 172.242.1.0/24, but 172.242.1.0/24 has its own specific route. Due to longest-prefix-match, the /24 route to 172.242.1.0/24 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 172.242.1.0/24 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: 172.242.1.0/24 is within 172.242.0.0/22 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 172.242.1.0/24 and let it follow the summary, or split the summary into two non-overlapping summaries that exclude 172.242.1.0/24. Ensure all subnets within a summary range follow consistent forwarding paths.
</reasoning>
<answer>
WARNING: Hole in summary detected. 172.242.0.0/22 (S) covers 172.242.1.0/24, but 172.242.1.0/24 has a separate specific route via a different next-hop. This creates inconsistent forwarding within the summary range. Fix: Align 172.242.1.0/24 with the summary next-hop 192.168.135.1, or restructure summaries to exclude 172.242.1.0/24. Ensure all subnets within a summary follow the same path.
</answer>