Checking if pool is up before using LB::SELECT in HTTP_REQUEST

Sure. You can do that.

 

when HTTP_REQUEST {
if { [active_members mypool] == 0 } {
HTTP::redirect "http://www.google.com"
}
else {
do something...
}
}

 

 

See the wiki entry for active_members for additional examples: http://devcentral.f5.com/Wiki/default.aspx/iRules/active_members.html

 

or

 

A a Code Share iRule posted by Hoolio: http://devcentral.f5.com/wiki/default.aspx/iRules/LTM_sorry_page_image_when_no_pool_members_available.html

 

How do I find the value of "mypool" before doing a load-balancing decision (or how can I handle this situation otherwise)? I want all of the variables of this connection to be filled in dynamically when the users triggers this iRule. i.e. virtual name, status if available pool name, status member names, status

If you want to be more dynamic you will have to go up a level and check in the CLIENT_ACCEPTED, doing is a bit more restrictive on what you can do though (HTTP::redirect is no longer available), but you can verify that the pool has members, if so it will pass through and you can do your LB::select in the when HTTP_REQUEST event. If no pool members are available, you route them somewhere else before the HTTP_REQUEST event and no further iRule processing is done:

See CLIENT_ACCPTED wiki entry at the bottom to see available commands within this event: http://devcentral.f5.com/wiki/default.aspx/iRules/CLIENT_ACCEPTED.html

when CLIENT_ACCEPTED {
if { [active_members [LB::server pool]] == 0 } {
pool website_down_pool
}
}

To add, if the virtual is marked DOWN on purpose the active_members will still respond as active.

 

 

 

Thanks

 

Bhattman

 

Thanks, thats exactly what I needed