You can configure the SMS server for HA while the servers are located in different
geographic locations. With this configuration, it is important to maintain the link
between both SMS servers to make sure the network provides enough bandwidth for the
heartbeat signal and the database replication.
By default, each node sends a heartbeat signal to its peer node every minute. If network
issues prevent both nodes from receiving three consecutive heartbeat signals, the
passive node initiates automatic failover even though it is possible for both server
nodes to be functional. This can result in two active SMS servers in the same node
configuration. To avoid unnecessary SMS HA server failover, ensure that the network
has a reliable link between the SMS servers with a bandwidth delay of less than 300
ms. Monitor the primary SMS server to make sure it is not overloaded and has adequate
resources including memory, file systems, and threads.