Forum Discussion

Adam_White_3627's avatar
Adam_White_3627
Icon for Nimbostratus rankNimbostratus
Sep 03, 2018

Outbound SMTP Relay

Hi there,

 

We are attempting to replace or IronPort email gateways by utilising our F5's.

 

Inbound, we have used the SMTP iApp, and secured this with client authentication, and this works fine.

 

However, for outbound, it doesn't seem to work. I have configured a virtual server, load balanced to our external 3rd party email servers for further routing. When I set the VS to have no client/server SSL profile, then the mail sends fine. However, when I add a server SSL profile, the F5 stops the connection straight away from our Exchange servers.

 

Has anyone else been able to achieve outbound, whereby the traffic from Exchange to F5 is unencrypted, and then the F5 encrypts from the VS to the nodes? Regards

 

Adam

 

BIG-IP
iApps
security
  • PeteWhite's avatar
    PeteWhite
    Icon for Employee rankEmployee
    Sep 04, 2018

    Often the problem is a silly one such as the pool members are listening on port 80 or the serverSSL profile does not support the same ciphers. Do a tcpdump to capture the traffic that is going to the server and start there. If you want us to check the config then post it.