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Nath's avatar
Nath
Icon for Cirrostratus rankCirrostratus
May 10, 2017

How to check if XFF is working

Anyone I am looking for a way to check if XFF is working in bigip aside from checking it to Wireshark. Server team keep on claiming that they still see the bigip SNAT IP on their end.

 

Thank you

 

-Nat

 

  • The pool member will still see the SNAT IP as the source IP. However, with XFF enabled the http request header will have the real client ip included as an additional field.

     

    Aside from checking the http profile/iRule that you've configured you could capture the server side request to confirm that the field is getting inserted but that would obviously require the use of tcpdump/wireshark.

     

    • Nath's avatar
      Nath
      Icon for Cirrostratus rankCirrostratus

      @Ryan i see, so I think all i can do is to check if they configured they server correctly.

       

    • Ryan_80361's avatar
      Ryan_80361
      Icon for Cirrostratus rankCirrostratus

      Yep, Check out K4816 and look towards the bottom of the page for the section titled Configuring the web server to extract the IP address from the HTTP header for extra info on configuring the web server.

       

  • The pool member will still see the SNAT IP as the source IP. However, with XFF enabled the http request header will have the real client ip included as an additional field.

     

    Aside from checking the http profile/iRule that you've configured you could capture the server side request to confirm that the field is getting inserted but that would obviously require the use of tcpdump/wireshark.

     

    • Nath's avatar
      Nath
      Icon for Cirrostratus rankCirrostratus

      @Ryan i see, so I think all i can do is to check if they configured they server correctly.

       

    • Ryannnnnnnnn's avatar
      Ryannnnnnnnn
      Icon for Altocumulus rankAltocumulus

      Yep, Check out K4816 and look towards the bottom of the page for the section titled Configuring the web server to extract the IP address from the HTTP header for extra info on configuring the web server.