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Forum Discussion

Mariusz_B's avatar
Mariusz_B
Icon for Nimbostratus rankNimbostratus
Feb 17, 2015

iRule - wrong variable definition ?

Hi all, I have the following iRule, which in terms of syntax is fine: when DNS_REQUEST { switch [IP::remote_addr] { "10.10.1.32/27" - "10.10.1.64/27" - "10.10.1.16...
application delivery
BIG-IP DNS
devops
iRules
Mariusz_B's avatar
Mariusz_B
Icon for Nimbostratus rankNimbostratus
Feb 27, 2015

Hello all,

 

Sorry for the delay with my feedback and thank you everyone for help. I managed to get some help from highly skilled iRule engineer, and below I am placing the final version. The biggest advantage of the iRule is that adding more clients, doesn't require any code modification. All I have to do is to modify 2 data groups; one called Clients_IPs (which is going to be universal, and which will be created for each wide IP.

 

when DNS_REQUEST {
 set mon "[class match -value [IP::remote_addr] equals Clients_IPs]"
 set ip "[class match -value  [DNS::question name] equals www.test.com_IP]"
 if { ( $mon ne "" ) && ( $ip ne "" ) } {
  if {[LB::status vs $mon up]} {
     host [getfield $ip "," 1]
   } else {
   host [getfield $ip "," 2]
   }
 }
}

Regards

 

Mariusz

 

JRahm_128324's avatar
JRahm_128324
Historic F5 Account
Feb 27, 2015
nice! I try to keep logic in the iRule, data in data-groups personally, but during development for rapid prototyping I put the data in the iRule in if/else or switch conditions.For simple situations where the list won't grow beyond a few entries, if/else or switch is fine.