Forum Discussion

レザ's avatar
レザ
Icon for Cirrus rankCirrus
Aug 24, 2022

Using reselect method to keep http session persistence

Hi,

I have two http servers behind a specific VIP, i'm using cookie method for persistency which working fine,

The problem I have is that when one of the my pool members goes down, the users who were logined on this pool member thrown out and have to log in again.

Can I use the RESELECT method in ActionOnDown section of my pool to avoid this problem?

if yes, shall i disable port/address translation on my virtual server?

thanks

application delivery
reselect
    • レザ's avatar
      レザ
      Icon for Cirrus rankCirrus
      Aug 24, 2022

      Hello 🙂

      Both virtual server and pool members are on same subnet, and service port is 80 (HTTP)

      for example:

      Virtual Server is: 192.168.23.254

      Server1: 192.168.23.180

      Server2: 192.168.23.181

       

      • Mohamed_Salah_'s avatar
        Mohamed_Salah_
        Icon for MVP rankMVP
        Aug 24, 2022

        Hello,

        you are right, you need to disable both translation to use this option based on the below article.

        Reselect option is only appropriate for:

        • Virtual servers with address and port translation disabled
        • Transparent pool members, such as firewalls, routers, proxy servers, and cache servers

        https://support.f5.com/csp/article/K15095

        It actually doesn't matter for the port translation. But regarding the address translaiton, the service will stop working because the address must be translated to the pool member.

         

        So based on this, unfortunately, i think you will not be able to use the reselect option.

  • Nikoolayy1's avatar
    Nikoolayy1
    Icon for MVP rankMVP
    Aug 24, 2022

    Better read the article for this feature https://support.f5.com/csp/article/K15095 as it has good description for this feature:

     

    ==========

     

    This option is only appropriate for:

    • Virtual servers with address and port translation disabled

      Note: This is the default for network virtual servers, such as wildcard IP Forwarding virtual servers.

    • Transparent pool members, such as firewalls, routers, proxy servers, and cache servers

      Note: Transparent devices can forward packets to destinations without regard for the state of the connection.

    • UDP virtual servers

      Important: Because this setting does not re-establish TLS or any other stateful protocol, you should not use it in a reverse-proxy deployment where pool members are stateful endpoints.

       

      ==========

    •  

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  • Nikoolayy1's avatar
    Nikoolayy1
    Icon for MVP rankMVP
    Oct 16, 2022

    If you managed to get the needed answers, please flag the question as answered.