Which device in the synchronization group initiates an iquery query?

Hi.

When you add newly gtm to include a synchronization group, you run gtm_add script on the local gtm.

As a result, local gtm_add establish a iquery connection to remote gtm and the script wipe out the configuration on the local gtm and pull newly configuration from the remote gtm.

Please take care, On which gtm you should run gtm_add script.

I hope this artcile would be helpful.

K13312: Overview of the BIG-IP DNS big3d_install, bigip_add, and gtm_add utilities (11.x - 15.x)

https://support.f5.com/csp/article/K13312

gtm_add

Description

You can use the gtm_add script to integrate a new BIG-IP DNS system into an existing sync group that has one 

or more remote BIG-IP DNS Controllers. The script replaces the current configuration files (bigip_gtm.conf, named.conf,

 and named zone files) on BIG-IP DNS on which it runs with the configuration of the remote BIG-IP DNS system in the specified sync group.

Note: The script presents a warning prompt confirming that you want to wipe out the current configuration on the local system.