Exchange problems on new vpn with asa an cisco routers.

[acleri]

Hi,

our network has 5 branch offices and 2 main offices.

To connect them we have tunnels gre that runs inside vpn ipsec tunnels.

The vpn are provided by cisco vpn concentrators 3005.

We changed our cisco vpn 3000 concentrators with new asa (main offices) and cisco routers with ipsec features on it (branch offices).

Since them we have problems on our exchange to deliver mail between our offices.

Our exchange servers run on virtual machines.

The remaining services are running well.

The mtu size on the tunnels gre have not been changed.

Does anyone have an idea what the problem is?

Thank you.

[dennisnieuwenhuyzen]

Hello,

Can you do a test with a lower MTU size and see what happens?

Gr,

Dennis

[acleri]

Hi Dennis,

problem solved.

On the cisco router on the branch offices there was a command that inspect the esmtp traffic that created problems on several exchange.

Thank you.