Before BIG-IP GTM can operate as an integrated component within your network, communications must be established between BIG-IP GTM and the other BIG-IP systems with which BIG-IP GTM must exchange information. The three scripts described in the table are used to establish these communications in specific instances.

BIG-IP systems use an XML protocol named iQuery to communicate with other BIG-IP systems using gzip compression. BIG-IP systems must exchange SSL certificates and be members of the same configuration synchronization group before the systems can share information using iQuery.

The gtmd agent on BIG-IP Global Traffic Manager (GTM) uses the iQuery protocol to communicate with the local big3d agent, and the big3d agents installed on other BIG-IP systems. The gtmd agent monitors both the availability of the BIG-IP systems, and the integrity of the network paths between the systems that host a domain and the local DNS servers that attempt to connect to that domain.

Communications between big3d and gtmd agents using iQuery

The gtm_add script is designed to be run on a BIG-IP GTM you are installing on your network, when you want to integrate the system into a previously created GTM synchronization group that includes at least one other BIG-IP GTM. The script copies the remote BIG-IP GTM configuration to the local BIG-IP GTM system.

The big3d_install script is designed to be run on a BIG-IP GTM you are installing on a network that includes BIG-IP systems of earlier versions. The big3d_install script connects to each BIG-IP system on your network, extracts the IP addresses of the devices, and automatically updates the big3d agents on all devices.

The bigip_add script is designed to run on a BIG-IP GTM you are installing on a network that includes BIG-IP systems of the same version. The bigip_add script exchanges SSL certificates with each of the other BIG-IP systems to authorize communication between the devices.