CirrocumulusNo Irule needed at all for this behavior.
Destination address (public IP) and translation address (private IP). Autodiscovery will not work only manual creation. Just implemented the solution and works like a charm (11.5.3 HF2)
Probing the private IP using bigip monitor that will sense all changes in LTM and will reflect in GTM. Also you can assign a GTM link to the underlying GTM servers (LTM VS) so that in case the link goes down also the associated Big IP virtual servers go down that will prevent from faulty DNS resolving.
https://support.f5.com/kb/en-us/solutions/public/13000/800/sol13827.html
You need to open the Iquery port 4353 for big3d monitoring to work on the self IP's, if you have problems with status updates using Iquery use iqdump on the command line with the server IP address (Self IP) of the neigboring LTM.
If you want to resolve differently based on the clients IP address, for example coming from the internet or from the local network use topology records. I created two topology records to prevent internal IP addresses to be resolvable from the internet (because it is used internally only).
Region private IP addresss Region the internet
Topology records Region Internet ==> Region Internet Region Internal ==> Region Internal
Create a wide IP for example www.f5.com with one pool. Within the pool select topology as the load balancing algorithm and as alternative use fallback and define a fallback IP, just to prevent the GTM to supply internal IP information to the internet. Within the GTM pool use to GTM virtual servers one with the private IP as the destination address and the other with the public IP destination address. The translated address will be the same. This way GTM will answer based on the location with the right IP, just like split DNS would do, just like that!!
No Irules no scripting just making use of the nice features GTM offers!! Cheers Marvin
