Forum Discussion
NorCalAdam_6796
Nimbostratus
NimbostratusRedirect to new pool/port when current pool offline
I am trying to send traffic to a different pool when all nodes in the current pool are down. It also needs to change port number when going to the other pool. Here is what I have so far, it seems to be sending traffic to new pool but not changing the port numbers. Can someone think of a better way to do this or help with my iRule?
when CLIENT_ACCEPTED {
if {[active_members pool1] == 0}{
if {[active_members pool2] > 0}{
pool pool2 x.x.x.x 48010
} else {
discard
}
}
}
when LB_SELECTED {
if {[active_members pool1] == 0}{
if {[active_members pool2] > 0}{
LB::reselect pool pool2 x.x.x.x 48010
} else {
discard
}
}
}
5 Replies
- Kevin_Stewart
Employee
Unless you've configured it otherwise, a pool is typically created with assigned port numbers, so you shouldn't have to change the port number in a pool statement (the pool sends traffic to the members in its member list on the assigned ports). Are you attempting to change the pool's assigned port number on the fly. 
NorCalAdam_6796Im just trying to get the application to work when it changes pool. Basically we are load balancing SQL, when all nodes in pool1 go offline I want traffic to go to pool2. Pool1 and pool2 use different ports for SQL.- Kevin_StewartThen you should be able to just use the pool command with the pool name (no IP and port specified) - assuming you've configured the pool members with the right ports.
You can probably also get away with just using the CLIENT_ACCEPTED event, unless your SQL connections are long-living and a pool might dies in the middle of a connection? 
Chris_Campbell1Cirrus
A much easier way to do this would be to use priority groups in your pool.
http://support.f5.com/kb/en-us/products/big-ip_ltm/manuals/product/bigip9_0config/ConfigGuide9_0-05-1.html (under "Specifying priority-based member activation")- Kevin_StewartAgreed Chris. Good call. You get roughly the same functionality.
