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Jim_Munroe_4488's avatar
Jim_Munroe_4488
Icon for Nimbostratus rankNimbostratus
Jul 24, 2006

Options for preserving real Source IP for SMTP IIS Logging w/ SNAT

Hello,

 

 

Looking for a way to preserve the real src IP address with in the IIS 6.0 SMTP logs. Using BigIP with SNAT to Load balance between multiple IIS based SMTP servers. Due to reporting restrictions we require the real server's IP address as the source rather than the IP address of the BigIP. We are running the latest version of 9.x.

 

 

Any ideas or input would be greatly appreciated.

 

 

Thanks,

 

 

Jim

 

 

application delivery
dev
devops
iRules

5 Replies

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  • Tom_Spector_50's avatar
    Tom_Spector_50
    Historic F5 Account
    Jul 24, 2006
    Hi Jim,

     

     

    Check out the iControl code share section for an IIS plugin:

     

    http://devcentral.f5.com/Default.aspx?tabid=38

     

     

    Cheers,

     

     

    Tom.
  • dennypayne's avatar
    dennypayne
    Icon for Employee rankEmployee
    Jul 24, 2006
    That plugin converts the X-Forwarded-For header (inserted in an HTTP profile) into the client address in the IIS logs. However, since Jim is trying to do this for SMTP he will not be able to utilize the HTTP header insert.

     

     

    Denny
  • Deb_Allen_18's avatar
    Deb_Allen_18
    Historic F5 Account
    Jul 24, 2006
    Assuming I understand your question...

     

     

    If you can can set the default GW for the SMTP servers so that return traffic is routed through the BIG-IP, then you can eliminate the SNAT of inbound client IP's, and SNAT only the outbound sessions initiated by the SMTP servers.

     

     

    HTH

     

    /deb

     

     

  • Kevin_82627's avatar
    Kevin_82627
    Icon for Nimbostratus rankNimbostratus
    Feb 25, 2010
    So is there no other way to accomplish this other than to set the default gateway back to the F5? (I mean for non-http protocols like imap and ldap.)

     

  • hooleylist's avatar
    hooleylist
    Icon for Cirrostratus rankCirrostratus
    Feb 25, 2010
    Hi Kevin,

     

     

    Changing the server's default gateway would be the simplest option in terms of LTM configuration.

     

     

    You could also try nPath where you have the servers respond back directly to the clients using the LTM VIP address. Try searching the forums or AskF5.com for details on nPath.

     

     

    Aaron