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Tcpdump and Ssldump Hanging

Hi Guys,

not sure, but when doing an ssldump or tcpdump, this occasionally hangs and does not give any output?

Any reasons why? Running version 12.1.2 HF2.

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USER ACCEPTED ANSWER & F5 ACCEPTED ANSWER

I had a problem where it hang just after I started a tcpdump. I found out it was connected to dns-lookups, so try adding option "-nn" and see if that helps.

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Comments on this Answer
Comment made 16-Jan-2018 by Adilkhan 65

Tried that, still not working...

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Comment made 16-Jan-2018 by jaikumar_f5 1684

Can you share your tcpdump command

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Comment made 16-Jan-2018 by Adilkhan 65

can share you my ssldump command

ssldump -ni 0.0 host 172.xx.xx.xx -nn

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Comment made 16-Jan-2018 by jaikumar_f5 1684

I tried to replicate yours, but I'm getting error as

ERROR: Length mismatch

Why not try this article, take the tcpdump first and write it to a file. Then do the ssldump to that pcap.

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Comment made 16-Jan-2018 by Adilkhan 65

no help at all, its a simple tcp/ssl dump command and its just hanging

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USER ACCEPTED ANSWER & F5 ACCEPTED ANSWER

Hello AdilKhan,

Try the following ssldump -nni 0.0 host 172.xx.xx.xx

If it doesn't work, I think you should open a case... something corrupted in your system.

You can also check this article about the recommandation & limitation of tcpdump on F5 systems.

https://support.f5.com/csp/article/K6546

Regards

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Comments on this Answer
Comment made 16-Jan-2018 by Jad Tabbara (JTI) 2360

FYI I'am running a 12.1.2 HF2 and it is working properly.

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Comment made 16-Jan-2018 by Adilkhan 65

I dont think anything is corrupted its more then 1 f5 versions/platforms, i know it does work, however its really hit and miss!

Must be something, which someone has seen? or something? Perhaps someone working at F5???

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