iRule for monitoring back-end server

Here is a great document on passive monitoring: http://lorimacvittie.sys-con.com/node/1483899/mobile, with an example at the end.

 

 

Here are a couple of simple iRules to get started:

 

 

Mark the pool member down if unable to connect to server:

 

rule server_down {

 

when LB_FAILED {

 

LB::down

 

}

 

}

 

 

Mark the pool member down upon a bad response from server:

 

rule bad_resp {

 

when HTTP_RESPONSE {

 

if { [HTTP::status] >= 500 } {

 

LB::down

 

}

 

}