Forum Discussion
NimbostratusLTM pool availability on a GTM irule?
How can we select LTM pool availability on a GTM irule? Something like this?
when DNS_REQUEST {
if { [active_members LTM_Pool ] =< 3 } {
pool GTM_Pool
} else {
return
}
}
6 Replies
JinshuCirrus
Thats the question exactly i have..
It's difficult from your code to figure out just what you're trying to accomplish, especially given the pool names in your example. Are you trying to select a pool of DNS servers to load balance the DNS query to based on availability of its members?
F5_Freek_243545Hello,
I'm trying to configure DNS decision based on LTM pool member availability.
GTM does not know about LTM's pool members, except in the case where you are load balancing a DNS query to a pool of DNS servers for resolution. In the case of a wide IP, GTM does know about LTM's virtual servers, and can intelligently reply with the IP address of one of those based on criteria you define on the wide IP and wide IP pools, such as geolocation, global availability, etc. You could have GTM reply with the IP address of the LTM virtual server, and then apply an iRule to the LTM virtual server that selects the appropriate LTM pool based on pool member availability.
- Amanpreet_Singh
Cirrostratus
Perhaps, not tested personally, but if your LTM pools contains web servers, you can make use of "HTTP monitor" on GTM to decide LTM_VS status directly from the pool members. BUT this depends how your setup is like. GTM should able to reach ltm pool members directly in your network.
/Aman
- Jinshu
I have created an external monitor using tmsh command to achieve this and it's working. Now GTM is making decisions based on the number of Ltm pool member availability.
-Jinshu
