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Forum Discussion

andrew_witherid's avatar
andrew_witherid
Icon for Nimbostratus rankNimbostratus
Apr 19, 2017

Applying a health monitor with DNS returned IP address

HI all,   i am looking to monitor a Destination selection based upon a DNS lookup, our current setup takes a HTTP request, extracts the Destination URL and preforms a DNS lookup, once the IP is r...
application delivery
iRules
LTM
Stanislas_Piro2's avatar
Stanislas_Piro2
Icon for Cumulonimbus rankCumulonimbus
Apr 19, 2017

Hi,

you can try with LB_FAILED event!!

when HTTP_REQUEST {
    if {[HTTP::uri] starts_with http} { HTTP::uri [findstr [HTTP::uri] [HTTP::host] [string length [HTTP::host]]} 
   set ips [RESOLV::lookup -a [HTTP::host]]

    Check if the first list element was empty
   if {$ips eq ""}{
       Input wasn't an IP address, take some default action?
   } else {
       Select the IP 
      node [lindex $ips 0]
   }
}

when LB_FAILED {
     The node timed out... 
}