Irule to set a pool on the basis of value in X-forwarded-for

Hi Yogeshtaneja, i would probably change your code to something like this.

when HTTP_REQUEST {
if { [HTTP::header values "X-Forwarded-For"] ne "" } {
         set clientip [getfield [HTTP::header X-Forwarded-For] "," 1]
         # set the variable ONLY if an X-FORWARDED-FOR header is there
   catch {
             # doing a catch to control any errors linked to the code 
             if { [class match $clientip equals test_ipranges_1] } {
                 pool pool1
               } elseif { [class match $clientip equals test_ipranges_2] } {
                 pool pool2
                } elseif { [class match $clientip equals test_ipranges_3] } {
                 pool pool3
               } else {
                 pool default
               }
            }
       }
                 pool default
             # in case the X-Fowarded-For was not properly set
             # or the catch provided an error
}

To be honest, i would have done this slightly differently, by putting in the datagroup, multiple entries of IPs (so in a way, merging your 3 datagroups into 1 here), and adding in the value, the pool you target. So in that case, you do a single check, and if it exists, you retrieve the destination pool in a variable and use pool $variable as the selected pool