Introduction to load balancing#
Cisco Unified Communications Manager (Cisco UCM) groups provide both call-processing redundancy and distributed call processing. You can distribute devices, device pools, and UCMs among the groups to improve redundancy and load balancing in your system.
A UCM group specifies a prioritized list of up to three UCMs. The first UCM in the list serves as the primary UCM for that group, and the other members of the group serve as secondary and tertiary (backup) UCMs.
Each device pool has one UCM group that is assigned to it. For example, Group 1 points to Device Pool 1, Group 2 points to Device Pool 2, and Group 3 points to Device Pool 3. When a device registers, it attempts to connect to the primary (first) UCM in the group that is assigned to its device pool. If the primary UCM is unavailable, the device tries to connect to the next UCM listed in the group, and so on.
Load balancing is a manual process on Cisco UCM, requiring you to perform the following tasks:
Add new, custom UCM groups and device pools.
Synchronize the groups and device pools into Automate.
Choose the appropriate group and device pool in the user management or phone configuration for the site. To create more than one configuration for a site, create at least two UCM groups, then associate a device pool to the appropriate UCM group.
To determine if load balancing is required for your network, you can check the current device traffic load in Cisco UCM, via System > Device Pool menu. When you click on the device configuration information for a specific device pool, the Device Pool Information field lists the number of members in the Device Pool. Compare different device pools to see if the members are evenly divided between pools.
To perform load balancing, see “Load Balancing Using Site Default Device Pool”.