I have been facing a very weird problem since I moved TMG behind ASA ( back to back)
Here is the case
I have single ASA 5540 with below interfaces
Gi0/0 Outside Interface
Gi0/1 Inside Interface
Gi0/1.1 TMG Interface
Gi0/2 DMZ Interface
The ASA inside interface is splitted into subinterface and configured with Vlan 3. I have trunk the swithcport at the switch side with below config
switchport trunk encapsulation dot1q
swicthcport trunk allowed vlan 2,3
switch port trunk vlan 2
switchport mode trunk
The TMG external interface is connected to a switch and is configured with vlan 3
Now here is the problem, frequently and suddently TMG stops pinging to the gateway ( IP of ASA sub interface). In order to resolve I have to reboot the ASA.
Please can someone help me to resolve this issue.