Avaya CMS High Availability (HA) ensures uninterrupted data flow between the communication server or switch and the CMS servers. In an HA configuration, two CMS servers connect to a single communication server or switch. This setup eliminates the traditional single point of failure between the CMS server and the communication server or switch.

Each CMS server independently collects data from the communication server and provides full CMS functionality. If one CMS server fails, loses its connection to the communication server, or must be brought down for maintenance, the other CMS server automatically manages all CMS operations.

Duplicate hardware plays a crucial role in preventing data loss resulting from hardware failures. By eliminating single points of failure, the HA system enhances reliability. The dual ACD link feature addresses potential ACD link failures, while the alternative ACD link improves overall link stability.

A C-LAN circuit pack or Ethernet port provides TCP/IP connectivity between the communication server and the CMS server. Each ACD link requires a dedicated C-LAN circuit pack or Ethernet port, with separate network routes to minimize the risk of failure.

The following figure displays a typical CMS HA configuration, featuring a primary or active server and a secondary or standby server: