Forum Discussion

wogo1905_288591's avatar
wogo1905_288591
Icon for Nimbostratus rankNimbostratus
Apr 21, 2017

VS change IP address

Hi Guys, On backup cluster I would like to create similar configuration for all application which are delivered by F5 LTM cluster. I'd like to connect backup cluster to the same VLAN assign self IPs, add nodes, create pools, ssl profile. But I don't know what should I do with Virtual servers. I can't create them with the same IP addresses. Can I create them with another IP addresses and in case of emergency just change IP addresses? What is your opinion?

 

4 Replies

  • What about integrate the backup devices with the active devices? As you said they can have the same vlan, so you can have a device group with 2 or more devices, in a sync-failover option. You can control in many ways which device is active, with one is next, and after that.

     

    Have a look in this solution for v13 (it also have the link for v11/12 in the solution):

     

    https://support.f5.com/csp/article/K63243467

     

  • As per above post, It looks like you wanted to create VIP, POOL, etc on backup node. Why to create same VIP on backup if both are in sync?

     

    F5 have very good option(iRule or Predictive method) to move traffic in case of Emergency.

     

    Let us know if you need more information.

     

    • wogo1905_288591's avatar
      wogo1905_288591
      Icon for Nimbostratus rankNimbostratus

      Sure I'm very interested. We have got 2 clusters. Fist one is in production with LTM only. Few days ago I deployed new cluster (with LTM, ASM, APM and AFM). This fist cluster is very critical and I would like to have some "emergency exit". On this cluster is few VS which are working on ports 443 and 25.

       

    • Samir_Jha_52506's avatar
      Samir_Jha_52506
      Icon for Noctilucent rankNoctilucent

      Well, What I understand here about "emergency exit"mean; If critical VIP goes down/unavailable. In that case traffic move to other VIP without any impact, right?

      This can be achieve via either Priority Group Activation(Load Balancing Method) or iRule.

      iRule--> Create two VIP on LB. Apply iRule to VIP-1 to move traffic VIP-2 if VIP-1 fails.

          when HTTP_REQUEST {
               if { [active_members [LB::server pool]] == 0 }
                   { HTTP::redirect "http://VIP2.com"
               }
              }
      

      Refer Link On Priority Group Activation

      Available Member(Pool_xxx) assign to VIP

      1) x.x.x.x:xx Priority 10 2) x.x.x.y:xx Priority 10 3) x.x.x.y:xx Priority 10

      4) a.a.a.a:pp Priority 20 5) a.a.a.a:pp Priority 20 6) a.a.a.a:pp Priority 20

      If minimum available member will be lesser then 1 then traffic will move to other pool group servers.