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PKX9_161380's avatar
PKX9_161380
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Jun 19, 2014

How to configure f5 smtp vip to show client IP

I have a smtp vip configured with autosnat, but requests show the floatingIP as the clientIP. How do i get this to show the real client IP

 

deployment
design

3 Replies

  • Cory_50405's avatar
    Cory_50405
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    Jun 19, 2014

    You'd have to disable SNAT in order for the SMTP server on the backend to see the original client IP address. In order for this to happen, your SMTP server would need a route in place that forced return traffic to the client back through the LTM. For example, setting the default gateway on the SMTP server to the self IP address on the LTM. This may or may not be feasible depending on your environment.

     

    • PKX9_161380's avatar
      PKX9_161380
      Icon for Nimbostratus rankNimbostratus
      Jun 19, 2014
      And just to confirm, outbound smtp from the pool members will be seen as the smtp VIP or is it the floating IP of the loadbalancer?
    • Cory_50405's avatar
      Cory_50405
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      Jun 19, 2014
      For the SMTP flows initiated by your SMTP servers, you will likely need to setup a separate forwarding virtual server. You can enable SNAT on the forwarding virtual server to ensure it leaves the LTM on whatever VIP you like by specifying a SNAT pool.