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Domai_23823's avatar
Domai_23823
Icon for Nimbostratus rankNimbostratus
Oct 23, 2018

LTM health monitor question

Hello Guys, I had a health monitor request from application team to make sure that the pool members were marked up if it was any 1,2,3,4 status codes. So in the receive string I used 

HTTP/1.(0|1) (1|2|3|4)
But now the requirement is to exclude 404, ie if the pool members returns 404 it should be marked down. So I came up with this - 
HTTP/1.[01] ([123]0[0-6]|401|402|403|[4]0[5-51])
Will the above work or can anyone suggest more elegant way for this receive string.

Thank you.

application delivery
LTM
  • tiziano_rosato's avatar
    tiziano_rosato
    Icon for Cirrus rankCirrus
    Oct 23, 2018

    Hi,

     

    you can configure the "Receive Disable String".

     

    This setting works like Receive String, except that the system marks the node or pool member disabled when its response matches Receive Disable String but not Receive String. To use this setting, you must specify both Receive Disable String and Receive String.

     

  • Andy_McGrath's avatar
    Andy_McGrath
    Icon for Cumulonimbus rankCumulonimbus
    Oct 24, 2018

    Try this, it works on https://regex101.com/ but not sure it the regex in F5 allows for negative/inverse matching 

    (?!404)

    HTTP\/1.(0|1) (?!404)(1|2|3|4)

    The ordering is important the 

    (?!404)
    needs to be in front of any positive match like 
    (1|2|3|4)

    You also might not need the escape character before the 

    /
    so it would be:

    HTTP/1.(0|1) (?!404)(1|2|3|4)