Setting up BIG-IQ®in a high availability configuration ensures that you always have access to the BIG-IP® devices you are managing. In a BIG-IQ high availability configuration, the BIG-IQ system replicates configuration changes since the last synchronization from the primary device to the secondary device every 10 minutes. If it ever becomes necessary, you can have the secondary peer take over management of the BIG-IP devices.
Before you can configure BIG-IQ systems for high availability (HA), you must have two licensed BIG-IQ systems.
For the high-availability pair to synchronize properly, each system must be running the same BIG-IQ version, and the clocks on each system must be synchronized within 60 seconds. To make sure the clocks are in sync, take a look at the NTP settings on each system before you add a peer.
If the primary BIG-IQ® in an HA pair is having any type of system issue, you might want to make the secondary BIG-IQ the primary system until you can fix the problem.
You can promote the secondary system to primary when you are logged in to either BIG-IQ system in the pair. This task describes how to promote the secondary BIG-IQ system while logged in to the primary BIG-IQ system.