Determine pools defined for WideIP

I'm not sure order is possible, but you can return the pools belonging to a wideIP:

 

 

when DNS_REQUEST {

 

log local0. "WideIP: [wideip name], Configured Pools: [pools -list]"

 

}

 

 

With the GTM pools command, you can also return the pools with a particular status (blue, green, etc)

 

 

http://devcentral.f5.com/wiki/default.aspx/iRules/pools.html Click Here

If you REALLY need order, I'm positive you could hack together some custom logic to order them somehow, it's just a matter of whether or not it's worth your time/effort and the cycles it will take in the iRule to execute all the custom logic each time the iRule is executed.

 

 

Colin

Thanks for the response! I had found the 'wideip name' variable.

 

 

I thought the pools -list returned 'all' pools, I'll try it in this context and see if it just returns those pools in the WideIP the rule is attached to.

 

 

I was looking at "GlobalLB::WideIP::WideIPPool" as a possible solution - but I'm not clear on the syntax to use.

 

 

Thanks,

 

Jeff

Test to be sure, but the description in the wiki indicates it will return only the pools attached to the wideip.

 

 

The GlobalLB::WideIP::WideIPPool method is for iControl, not iRules, and will have to be called externally from a dns request.

Thanks to everyone for the help - I did get this working with the following (rather simple) code:

 

 

when DNS_REQUEST {

 

set wip [wideip name]

 

set pl [pools -list]

 

set counter 1

 

 

foreach p $pl {

 

set pname($counter) $p

 

incr counter

 

}

 

 

log local0. "WIP: $wip, pool1: $pname(1), pool2: $pname(2), client: [IP::client_addr]"

 

 

If the Client IP (DNS server) is from the DR subnet, send

 

the request to the DR pool (2)

 

 

if { [IP::addr [IP::client_addr]/16 equals "xx.xx.xx.xx"] }

 

{

 

pool $pname(2)

 

} else {

 

pool $pname(1)

 

}

 

}

 

 

One thing to note about the 'pools -list' command, if there is a 'Last Resort Pool' defined in the WideIP - and the pools are not in a 'green' state - only the Last Resort Pool is returned by the command. Seems a little strange . . .

 

 

Thanks again,

 

Jeff

 

Why do you think the later is strange? When would you want the 'pools -list' command to return an unavailable/disabled pool?

According to the documentation:

 

 

pools -list

 

* Returns a list of pools in the wideIP.

 

pools [blue|green|yellow|red|gray]

 

* Returns the number of pools in the wideIP in the specified state.

 

pools -list [blue|green|yellow|red|gray]

 

* Returns a list of pools in the wideIP in the specified state.

 

 

It looks like -list flag should list all pools regardless of state, since I can then qualify it to only see pools of a specific state if I want to.

 

 

I was also pointing out that the results of the command are different if I have a 'Last Resort Pool' defined in the WideIP - from when I don't. I still think it's a bit strange ;-)

 

 

Also - there are times (in our environment anyway) where I need to get DNS (WideIP's) setup before the hosts are actually available. In this case - they are DR servers that I need to setup DNS for, but the servers aren't yet available for monitoring to succeed. And I don't always rely on the GTM to determine health - I want it to give out the correct IP's. We have other devices (load balancing) that can route based on health status.

 

 

So . . . I am looking for the command to return all pools in this case - regardless of state . . .

 

 

Jeff