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Mangled packets??

I never heard of such a thing. NetHealth monitor on the LAN is reporting:

Mangled packet from (ip addr)

ASN length too long

bad header

All Catalyst 29XX switches being used.

All we know so far is that the station in question is a Win2k. Anyone heard of this?

Community Member

Re: Mangled packets??

Hm. ASN length is too long? ASN.1 is "Abstract Syntax Notation 1) which is the ISO's standard for sending messages (read: data) across a network. It's composed of two parts: syntax and the actual encoding.

For more fun reading, check out: ISO 8824/ITU X.208 and ISO 8825/ITU X.209.

*But* I am guessing that NetHealth is misinterpreting the packets as ASN. Instead, I'd suggest focusing on the "mangled" packet thing. NetHealth has a packet decoder, might want to bring that up, see a "mangled" packet, and check why it thinks it's mangled.

By comparing the actual frame against standards, you can get some idea about whether the problem is with the switch (bad forwarding?) or with the NIC or PC sending the frame itself.

Community Member

Re: Mangled packets??

Thanks J-lau. I found a document that referred mangled packets to a possible cable problem. I will take your advise and investigate the packet contents though. We have a cable analyzer on order, so first things first.

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