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Forum Discussion

Prasad4u's avatar
Prasad4u
Icon for Nimbostratus rankNimbostratus
Dec 02, 2015

F5 Health monitor time interval and time out issue.

Hi All,

 

In our environment, Health monitor configured in such a way that the Time Interval as 5 secs and Time Out value as 4 secs.

 

As per F5 API, time out value should be 3xn+1 i.e. 16 but few of our engineers configured in such a way.

 

Please help me in understanding, how health monitor/F5 will behave if we configured as above.

 

MOnitor type : SIP

 

Mode : TCP

 

Thanks in advance.

 

Regards, Prasad

 

application delivery
BIG-IP
LTM

2 Replies

  • Vik_K_236702's avatar
    Vik_K_236702
    Historic F5 Account
    Dec 02, 2015

    Hi Prasad

     

    Ideally the timeout value should be higher than the time interval. There is no reason whatsoever to keep it 4 seconds. Please work with your team mates to get it changed. Probably they got confused by the fact that in the default timeout we set i.e., 16 seconds, LTM checks against the monitor for 4 times, they might have set it 4.

     

    The timeout should always be higher than the time interval set. If you cannot wait long, probably make it 6 if not more. I dont know what the member status would be in your case. Can you somehow test it and let us know.

     

    Another link I got on time interval and timeout discussions .

     

    https://devcentral.f5.com/questions/monitor-settings-interval-timeout-etc

     

    Regards, Vik

     

  • JG's avatar
    JG
    Icon for Cumulonimbus rankCumulonimbus
    Dec 02, 2015

    Values not conforming to the recommended 3xn+1 can actually trigger serious problems (bidg crashing) in v11.6.0.