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fergusone_29406's avatar
fergusone_29406
Icon for Nimbostratus rankNimbostratus
Oct 26, 2010

Headers truncated at 4096bytes

A problem has arisen with a virtual server over the last few weeks. When testing an application the user recieves 400 Bad Requests errors in their browser. From my testing it looks as though Headers are being truncated at 4096 bytes when leaving the Big-IP bound for the pool member. If a Header is 4097 bytes or above the 400 Bad Request error occurs.

 

 

Testing direct to the pool member, missing out the Big-IP, the error does not occur with Headers over 4096 bytes.

 

 

Has anybody else experienced this type of issue?

 

 

Regards,

 

 

Ewan
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  • hooleylist's avatar
    hooleylist
    Icon for Cirrostratus rankCirrostratus
    Oct 27, 2010
    Hi Ewan,

     

     

    Are you running any modules on the virtual server? I thought LTM could handle up to 32k byte length headers by default:

     

     

    SOL8482: Error Message: HTTP header exceeded maximum allowed size of

     

    http://support.f5.com/kb/en-us/solutions/public/8000/400/sol8482.html

     

     

    Have you tried comparing a tcpdump of the LTM clientside and serverside HTTP request? If so, do you see the long header being truncated? If you do, I'd suggest opening a case with F5 Support to investigate the issue.

     

     

    Aaron