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Forum Discussion

Jan_Rockstedt_4's avatar
Jan_Rockstedt_4
Icon for Nimbostratus rankNimbostratus
Jan 14, 2014

VIP for SMTP to see the real client ip.

Hi all,   We have setup a VIP for port 25 and use the below irule together with data group to restrict the access. But we do not see the real client ip addresses I guess because of SNAT. Any sugge...
Vitaliy_Savrans's avatar
Vitaliy_Savrans
Icon for Nacreous rankNacreous
Jan 14, 2014

Hi Jan, after you fixed routes to F5, go to:

Local Traffic/Virtual Servers/Virtual_server_name/Properties/

put "none" to Source Address Translation. You will see real client IP in logs of SMTP servers.

P.S. remember that in this case F5 must be default GW for smtp servers.

pete_71470's avatar
pete_71470
Icon for Cirrostratus rankCirrostratus
Jan 14, 2014
You could also use nPath if the F5 doesn't need to be traversed for mail server responses (e.g., not modifying responses on the F5, etc). This is what we do here and it works like a charm.