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Jimmy20's avatar
Jimmy20
Icon for Nimbostratus rankNimbostratus
Jun 10, 2020

Need help on Understanding mentioned iRules

Hello All,   Requesting help to understand below iRules.   1) iRule-1   when HTTP_REQUEST {  # save hostname for use in response  set fqdn_name [HTTP::host] } when HTTP_RESPONSE { ...
application delivery
iRules
Jimmy20's avatar
Jimmy20
Icon for Nimbostratus rankNimbostratus

Hello CJ,

 

Could you please explore more on below iRule :

 

when HTTP_REQUEST {

    set app_pool [class match -value -- [string tolower [HTTP::uri]] starts_with services_redirect_class_8085]

    if {$app_pool ne ""} {

      pool $app_pool

    } else {

     return

    }

  }

 

As per your previous reply, I understand...that the rules are searching for a pool name based on URI OR within Data Group, If found (not equals empty), request are send to this pool name, otherwise return... (but return to where ...back to search criteria..?) 

cjunior's avatar
cjunior
Icon for Nacreous rankNacreous
Jun 23, 2020

Hello,

 

The "return" command tells to exit/break from event HTTP_REQUEST. In your iRule the return looks disposable since it don't have code to escape after "return".

 

Example when return could be useful:

{
    If { condition 1 matches } {
      Do something here
    } Else {
      return
    }
 
    # This and lines below are reacheable only if condition 1 above is met
    If { condition 2 matches } {
      Do something here
    }
    Do something here
    and on
}

Regards