We are currently running BIG IP DNS on the BIG IP 2000 and are in the process of standing up new i2600 series.
The end game is to swap these out one for one and I am looking for thoughts on the best way to accomplish this.
I've seen the migration process outlined but I was looking to approach this in a different way. My thoughts are, we add the new i2600 to the sync group, allowing all GSLB and DNS records to sync to the new i2600. From there, within a maintenance window, I would just update our NAT translation to point the current public IP for our NS servers to the listeners on the new i2600. This way, if there are any resolution issues, a quick NAT update would move everything back to the old 2000 series. Is this a viable option?
If you don't want to use the platform migrate option (https://support.f5.com/csp/article/K82540512). I think what you are trying will work. You will need to make the old GTM devices the same version as the new ones:
Just a note:
Also you can just export and import the zone runner config uzing zone transfer: