Assigning multiple iRULES to a VIP

If you do not use Priority command, then all iRules are silently allocated priority of 500. All equal. Then the order in which they are mapped to Virtual Server will have significance, as you already guessed. But this is bad practice with no benefits. Occasional bugs due to config reload can mess up the order those rules are mapped to your Virtual Servers.

Note that only the current event that is taking place will be affected by

priority

A snapshot of how multiple iRules are actually processed will look as follows

RULE_INIT event of iRule that has priority (or event priority) set to 1
...
RULE_INIT event of iRule that has priority set to 999
...
HTTP_REQUEST event of iRule that has priority set to 1
...
HTTP_REQUEST event of iRule that has priority set to 999
...

Does LTM support Nested irule for example calling an another irule from the irule?

• With standard TCL iRules, nope. Maybe you can do it with iRulesLX but cannot confirm.

Regards,

Thanks a lot Hannes for your reply. If suppose there are two iRULES first one for inserting the client IP and second one for content switching based on URI?

Could you please help me to know in which order I have add the iRULES?

Regards, Thiyagu

Why do you need 2 irule for the above scenario, both take place in http request event, can't you achieve both in a single Irule. Or am i missing something here. Can you post both your Irules.

Hi Jai, Here is the irules: First, when HTTP_REQUEST { set rd "%[ROUTE::domain]" set client_ip [string map "$rd \"\"" [IP::client_addr]] HTTP::header insert srcaddr $client_ip }

Second, when HTTP_REQUEST { if {[HTTP::uri] starts_with "/uri1" } { pool pool1 } elseif {[HTTP::uri] starts_with "/uri2" } { pool pool2 } elseif {[HTTP::uri] starts_with "/uri3" } { pool pool3 } }

Would I able to merge both the irules without the flow of the application to the application servers based on the URI?

Regards, Thiyagu

yes that should work,

when HTTP_REQUEST {
set rd "%[ROUTE::domain]"
set client_ip [string map "$rd \"\"" [IP::client_addr]]
HTTP::header insert srcaddr $client_ip
if {[HTTP::uri] starts_with "/uri1" } {
    pool pool1
  } elseif {[HTTP::uri] starts_with "/uri2" } {
    pool pool2
  } elseif {[HTTP::uri] starts_with "/uri3" } {
    pool pool3
  } else {
   pool default      
}
}