GTM Migration Exercise to DR
We are going to migrate GTM services to our DR site your input is highly appriciated if you have any aritcle and document any suggestion please included your Guide line.
Azim_IIPL How are your GTMs configured? Typically with GTMs when you have a Production and DR site you run both GTMs together with both resolving DNS queries and syncing configuration between themselves. The reason for this type of setup is because GTMs are inherently redundant because they act as individual authoritative responders so if one fails the other one still keeps responding to DNS queries. If your GTMs are configured in the typical setup then you should have nothing to do when you start using DR because that GTM should have always been responding to DNS queries and should have a updated configuration.
I would also recommend considering the F5 training class on DNS/GTM or professional services. We have many customers that ask for assistance on the first go, and we document the process together so that the steps can be followed in future exercises. However, as Paulius mentioned, if properly configured, any DNS/GTM failover should be automatic. Manual failover makes sense if you want to simulate DR testing and force down an entire datacenter and associated objects.
If you are adding a new datacenter, then of course, you need to add a dedicated GTM, add the new GTM to the GSLB sync group, add a new datacenter object, create new configurations using DR resource IP addresses, and reconfigure any WIPs to make use of the new objects. There is no guide for how to architect this nor how to configure, as it really depends on the environment.