Forum Discussion
David__Pasch
Altostratus
AltostratusBig-Ip DNS - Topology LBing and Return-to-DNS
DevCentral, I absence of a lab to test this, I am posting this question to you. If I have a WIP set up for topology load balancing, with three pools. topo records for:
region 1 to pool 1 score 20
region 2 to pool 2 score 20
unmapped to pool 3 score 20
If return-to-dns is ONLY set on pool 3, will the other pools also return-to-dns? OR Will I need to create lower cost topology mappings for region 1 and 2 to go to pool 3, so they can use the Return-to-DNS feature?
Like:
region 1 to pool 1 score 20
region 2 to pool 2 score 20
unmapped to pool 3 score 20
region 1 to pool 3 score 10
region 2 to pool 3 score 10
Thanks in advance!!!
Leonardo_SouzaCirrocumulus
Forget the topology part for a few seconds.
If you had global availability, so pool1 -> pool2 -> pool3 (with return to DNS). If pool1 can't handle the request, the GTM will go for pool2 and not bind. However, if you have return to DNS in pool1, it will go to bind, so never reaches pool2.
Now back to topology...
If you say to send traffic to pool1 only, and that pool can't handle the traffic, it will not send to pool3. To do that, you have to play with the topology score, and have a record to pool1 and one to pool3.
There is also the last resource pool, but that is more for when everything is down.
https://support.f5.com/csp/article/K15258