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speachey's avatar
speachey
Icon for Cirrus rankCirrus
Feb 21, 2020
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default http monitor (v14.1.2.2) causing "HTTP/1.1 400 Bad Request" on pool member

the f5 marks the pool member as up, but sys admins are complaining about excessive "bad request" logs caused by the default f5 http monitor of a server.   vip service port: 80 pool listen port...
application delivery
LTM
  • Grumpy_Cat's avatar
    Grumpy_Cat
    Feb 21, 2020

    Hi speachey,

     

    This is normally caused when the request doesn't comply with HTTP v1.1 standards, i.e. missing Host header. Considering this is the default monitor it's likely that your web server is expecting a more specific request.

    Two helpful ways to troubleshoot this issue is to enable logging on the pool member in question, and/or mimic the health monitor using cURL - see the man page for more details.

     

    Let me know if that helps.

     

    Kind regards

    Ben

Grumpy_Cat's avatar
Grumpy_Cat
Icon for Cirrus rankCirrus
Feb 21, 2020

Hi speachey,

 

This is normally caused when the request doesn't comply with HTTP v1.1 standards, i.e. missing Host header. Considering this is the default monitor it's likely that your web server is expecting a more specific request.

Two helpful ways to troubleshoot this issue is to enable logging on the pool member in question, and/or mimic the health monitor using cURL - see the man page for more details.

 

Let me know if that helps.

 

Kind regards

Ben