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Jeff_Morrison_4's avatar
Jeff_Morrison_4
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Dec 03, 2008

Load Balance IMManger

I have a pair of Symantec IMManager servers that perform as a proxy to monitor IM chats. I have set up the LTM to pass the traffic on port 1863 (MSN) to the backend servers. All is working except I need the backend server to see the clients IP address and not the LTM address.

 

 

How can this be done?

 

 

Thanks in advance.

 

 

Jeff

3 Replies

  • clim_16682's avatar
    clim_16682
    Historic F5 Account
    Try this:

     

     

    (1) Disable SNAT (at Global or Virtual Server level) - this prevent the egress traffic source address to be snat-ed to LTM IP address.

     

     

    (2) Make sure the IMManager default route is point to LTM (Self-IP)

     

     

    (3) Persistence may be required.

     

     

    Hope it work for you.
  • This should probably go in the Config forum rather than iRules, but LTM by default preserves the client IP address. If it is not then you must be using SNAT. If LTM is the servers' gateway then you shouldn't need to, but if it is not, then you have to SNAT to preserve the routing, otherwise the servers will try to respond through their gateway back to the client directly. The client will then drop the packet because it does not have a session with the server, but with the virtual on the LTM.

     

     

    With HTTP you can insert an X-Forwarded-For header which contains the original client IP address that the server can then log. I don't know if there is any similar mechanism for the protocol involved here, but I suspect not.

     

     

    So bottom line is if you need to see client IP in the server logs you may have to redesign your network so that LTM is the default gateway for the servers.

     

     

    Denny
  • Colin_Walker_12's avatar
    Colin_Walker_12
    Historic F5 Account
    Good description Denny, thanks! Also - moved this to the ADC forums where it belongs.

     

     

    Colin