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rich1977_120837's avatar
rich1977_120837
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Aug 13, 2014

Keep Source IP

Can someone explain to me how to keep the source IP for external incoming SMTP traffic into our VIP for Exchange? The issue is the traffic looks like its coming from the self IP of the F5 therefore to Exchange it looks like local traffic so its using the wrong recieve connector. I need all traffic coming into this VIP to retain its original source IP. Can someone expain how to do this? My version is 11.5. Thanks!!

 

  • You can certainly use a SNAT pool. I thought your requirement was to see the original client IP address.

     

  • On the LTM, you'll need to disable source address translation (SNAT) on the virtual server. Then the LTM will pass the traffic through with a source IP address of the connecting client.

     

    In order for this to work, the Exchange server will need to route back to the client through the LTM. So either you'll need to set the default route on your Exchange server to a self IP address on your LTM, or you'll need to do some policy routing in your network somewhere.

     

  • So that is the only way to preserve the source IP? What about setting up a snat pool for this? Is that an option? I just need a way for the traffic to my exchange servers to not look like its coming from the self IP of the LTM. I really dont care what source IP its translated to as long as its not the self IP.

     

  • You can certainly use a SNAT pool. I thought your requirement was to see the original client IP address.