In opHA, each server has a role in the system to keep the data synchronised between the servers.

In the following tables you can see all the roles and their functions.

Roles

opHA Server Role	Meaning
Main Primary	All collected data is accessible on the Main Primary server giving users a single place to access all information.
Secondary Primary	The Secondary Primary provides redundancy for primary servers.
Standalone	If a server has not been added to a opHA cluster, it is a Standalone. When you first install NMIS on a server, it is a Standalone.
Poller	opHA provides the Poller role to scale data collection horizontally across multiple Pollers, and then have those devices report up to one or more Primary servers.
Mirror	The Mirror role provides redundancy for poller servers. A mirror is paired with a poller and polls the same devices as that poller, if the Poller goes offline, the Primary will collect all the data from the Mirror automatically.

Primaries means all the servers that are Main Primaries or Secondary Primaries.

Peers means all the servers that are Pollers or Mirrors.

Functions