Forum Discussion

Dayesh_263997's avatar
Dayesh_263997
Icon for Nimbostratus rankNimbostratus
Aug 15, 2018

Client and backend server communication.

Hi All,

 

Just wanted someone to clarify if my understanding is correct.

 

Scenario when the client is talking to the VIP (Source is Client IP and Destination is VIP). As the packet reaches LTM, with SNAT configured, the source IP becomes the SNAT IP and backend server becomes the destination IP.

 

Now when the server replies to the SNAT IP (i.e Server IP is the source and Destination is the SNAT IP) and from there on my understanding says VIP will be the source IP and client IP will be the destination for the reply to reach the client.

 

Please confirm if the understanding of "VIP will be the source IP and client IP will be the destination" is correct.

 

Thanks, Dayesh

 

application delivery
LTM
  • youssef1's avatar
    youssef1
    Icon for Cumulonimbus rankCumulonimbus
    Aug 15, 2018

    Hi.

     

    You right.

     

    Follow this use case:

     

    • client send request to vip.
    • F5 process the request and forward request to backend (snat automap is activate ) with vip IP if it is a cluster or sip IP if standalone.
    • the backend respond to source ip ( f5 snat ip).
    • then F5 respond to client IP.

    Let me know if you need more details.

     

    Regards

     

    • Anirban's avatar
      Anirban
      Icon for Nimbostratus rankNimbostratus
      Jun 07, 2023
      • I took a packet capture in client. Found backend pool member ip is responding with c)ient in same tcp session.

      What is wrong in F5