Cisco 3745 + 2 NM-16ESW modules breaks IP routing
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Description
Hello,
I am running a Cisco 3745 12.4(25d) in a GNS 3 topology. Inserting a single NM-16ESW works fine, but adding another one in slot 2 breaks the IP layer setup in my administration VLAN interface :
# debug ip packet
# ping 192.168.1.3
*Mar 1 00:04:04.139: IP: tableid=0, s=192.168.1.2 (local), d=192.168.1.3 (Vlan200), routed via RIB
*Mar 1 00:04:04.139: IP: s=192.168.1.2 (local), d=192.168.1.3 (Vlan200), len 100, sending
*Mar 1 00:04:04.143: IP: s=192.168.1.2 (local), d=192.168.1.3 (Vlan200), len 100, encapsulation failed.
However, the switching still works fine, as hosts are able to communicate with Internet. Removing the second module and rebooting makes everything back to normal. Could someone help me ? Thanks !
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Research direction
Start by reproducing the reported GNS3 topology with a Cisco 3745 running 12.4(25d) and one versus two NM-16ESW modules. Compare the IP debug output and routing behavior, then identify the Dynamips component responsible for the encapsulation failure and verify the fix against both module configurations.
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Assessment
- Domain
- networking
- Issue type
- Bug
- Difficulty
- 5/5
- Estimated time
- Over a week
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 20/100