Forum Discussion
Richard_22613
Nimbostratus
NimbostratusF5 Lync iApp with Cisco firewalls
I have configured the Lync iApp on a F5 LTM in our DMZ behind a Cisco firewall.
The client AV traffic goes through the firewall, hits the F5, which sends it on to one of the edge servers (in the...
Richard.... one solution would be to point the default gateway of the Edge servers to the BIG-IP Self-IP, and the default gateway of the BIG-IP to the firewall. This will route connections that are being load balanced by the BIG-IP correctly without having to SNAT anything.
You will also have to deal with connections that are being sent directly to the Edge Servers themselves (and not sent to the BIG-IP for LB). The return traffic from the Edge servers will then be sent (assymetrically) to the BIG-IP since that is the DFGW of the Edge servers. To get the BIG-IP to pass this return traffic on through to the firewall, create a forwarding VIP with loose connections enabled. This effectively gets the BIG-IP to act as a stateless router for the return traffic of connections sent directly to the Edge Servers.
Dave_20158Ryan - Thank you so much for this information. We ran into this exact issue with the asymmetric routing and I could not understand why the BIG-IP was not forwarding the traffic. Once I created the new fast-L4 profile and enabled loose initiation and loose close, everything worked perfectly.