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SuppEsp_AX's avatar
SuppEsp_AX
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Jun 29, 2026

Doubt adding F5 in sync-group

I need to replace an LTM-GTM cluster. I will replace the standby node first. The sync-group are 4 devices. My question is about adding it to the GTM sync group. Should I run only the gtm_add command, or do I also need to run the bigip_add command? I'm not sure whether joining a sync group requires both commands or just one of them. I'd also like to know where each command should be executed. I understand that gtm_add is run on the new node being added, but is bigip_add also run on the new node? how can i delete the old nodes for the sync-group when its donde the change?

2 Replies

  • the ha device group is meant for device pairing within single data center.

    for the gtm/dns sync between dc, you need to configure separate sync.

    https://techdocs.f5.com/en-us/bigip-17-5-0/big-ip-dns-implementations/adding-a-new-big-ip-dns-to-a-big-ip-dns-synchronization-group.html#overview-adding-a-big-ip-dns-system-to-a-big-ip-dns-synchronization-group

    • SuppEsp_AX's avatar
      SuppEsp_AX
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      Scenario is: 4 serie i2600 forming sync-group GTM. Being two diferent cluster HA active/standby LTM. First ill change one pair and another day the another.

       

      My idea for migrating an LTM/GTM pair from the iSeries platform to the rSeries platform is as follows:

       

      We used same cables from i series and same names and IPs to do it easier to customer

       

      First, I disconnect all the cables from the standby iSeries unit. The active iSeries unit will remain active in standalone mode.

      Next, I connect the interfaces used for the synchronization and failover network from both iSeries appliances to the new rSeries appliances. The HA pair has already been configured on the new rSeries units, so one will be active and the other will be in standby.

      Once the standby rSeries node is in place, I connect all the service cables to it. After all the service cables have been connected and I have verified that everything looks correct (ARP entries, pools, etc.), I proceed to run the bigip_add and gtm_add commands against the active iSeries node.

      It is important to note that the iSeries and rSeries appliances will never form an HA cluster with each other.

      After running both commands, I verify that everything is operating correctly before forcing the active iSeries node offline and allowing the rSeries node to become active.

       

      If I face any issues while running the bigip_add or gtm_add commands, since the new rSeries nodes use the same hostnames and IP addresses as the previous iSeries appliances, I may need to remove the trusted certificates associated with the old appliances from the other BIG-IP devices before attempting the commands again.

       

      Anything to keep in mind? or any potencial issie doing like that?? Would it be necessary or recommended to temporarily take the GTM cluster being migrated out of service, or is there no significant risk in keeping it operational?

       

      Its my first GTM migration in a bit lost.