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Unexpected forwarding decision | DROP

DanDan
Level 1
Level 1

Hello ACI people!

I came across a strange issue today.

I have a jumphost living in the fabric. From that jumphost I tried to reach two different hosts in the same subnet, external to the fabric.

I can ping one of them from the jumphost with no issues, however the other host is unreachable.

I did elam capture and ftriage and I can see it is dropped because of a missing contract.

For some reason first hop Leaf thinks that my destination is in a different EPG, where we do not have a contract in place so it drops the packet.

When I check the iproute on the Leaf, for both destinations it shows our ASA, as it should.

Have anyone experienced this before?

We are running on release 5.2(7g).

DanDan_0-1700509682104.png

Leaf is somehow classifying the external IP address as an internal host in a different EPG, which is absolutely incorrect.

Thank you for any thoughts.

1 Accepted Solution

Accepted Solutions

DanDan
Level 1
Level 1

Alright, issue is now solved!

https://www.cisco.com/c/en/us/solutions/collateral/data-center-virtualization/application-centric-infrastructure/white-paper-c11-739989.html#L3Outendpointlearningconsiderations

 

DanDan_0-1700515646925.png

I had a stale endpoint on the border leaf, once I manually cleared the entry , it worked just fine.

I hope this helps to someone in the future.

Cheers.

View solution in original post

1 Reply 1

DanDan
Level 1
Level 1

Alright, issue is now solved!

https://www.cisco.com/c/en/us/solutions/collateral/data-center-virtualization/application-centric-infrastructure/white-paper-c11-739989.html#L3Outendpointlearningconsiderations

 

DanDan_0-1700515646925.png

I had a stale endpoint on the border leaf, once I manually cleared the entry , it worked just fine.

I hope this helps to someone in the future.

Cheers.

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