Monday, August 19, 2013

GNS3 bug: %OSPF-4-ERRRCV: Received invalid packet: Bad Checksum

SYMPTOM:
I've got an error when testing a simple OSPF network with GNS3 0.8.4-RC4.
%OSPF-4-ERRRCV: Received invalid packet: Bad Checksum from X.X.X.X, INTERFACE_ID

WORKAROUND:
1. Open topology.net from an editor
2. Change "Sparsemem = True" to "Sparsemem = False"

NOTE
The problem seems to be fixed on dynamips-0.2.10. GNS3 0.8.5 and Dynamips-0.2.10 with sparsemem option does not cause a problem.

3 comments:

  1. I tried this fix and it did not seem to help.

    I am running GNS3 0.8.5 with IOS image: c7200-advipservicesk9-mz.152-4.S4.image.

    I am running Dynamips version 0.2.10-x86/Windows stable.

    Do you have anything else that I can try?

    kc6alg@comcast.net

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  2. Hello all,

    I have noticed that this error pops-out every 30 minutes, so I think it has something to do with periodic LSA flooding (the OSPF feature, usually used for compatibility with some legacy routing protocols). By default in OSPF the aging timers are set to 30 minute, but we can disable this on individual interfaces with a command:

    >interface FastEthernet 0/1

    >ip ospf flood-reduction

    "Any LSA transmitted from this interface will be marked as Do Not Age, and therefore periodic LSA re-flooding is not necessary."

    More info on this at: http://bradhedlund.com/notes/ospf/

    I haven't tried it yet on my GNS, but I think this is the case. Although there shouldn't be any errors and it seems to be simply a bug, but for your own peace of mind you can just disable it. Hope it works for you guys.

    Val

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  3. In my case, the interval was more often than 30 minutes, so it seems there are multiple conditions for the error. What I can suggest is changing Dynamips version. Did you try Dynamips 0.2.8-community or any other versions?

    http://www.gns3.net/dynamips/

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