High Availability (HA) Failover

Overview

The High Availability (HA) failover feature for AMM 2.17 provides replication to a secondary AMM that can support failover, in the event that the primary AMM is offline due to a data center power or connectivity failure. The HA service runs on top of a fully operational AMM system. It is designed to simplify the backup process and increase reliability for deployed AMM servers.

HA failover is an advanced feature that can only be configured by an administrator. For more information, refer to HA Configuration .

This topic provides an overview of how HA failover works.

An AMM HA configuration is composed of two servers:

• Primary server: the ‘active’ server that AirLink gateways and routers report to and users can access via their preferred web browser.
• Secondary server: the ‘standby’ server where the file system and databases are being replicated from the Primary server’s. The AMM services on the Secondary server are all stopped and disabled (except MySQL). Note that users cannot access the Secondary server for day-to-day use.

Under normal operation the Primary Server is replicated to the Secondary server:

In the event that the Primary server fails, the Secondary server will take over, stopping the AMM services on the Primary server and initiating the services on the Secondary server:

Note that the secondary server can only protect the primary for one failover occurrence. Once a failover has occurred, restoring the failed server does not restore HA failover functionality. In this situation the two servers must be reconfigured into two standalone AMMs, after which they can be reconfigured for HA failover. These configuration procedures must be performed by the Sierra Wireless Customer Support and Professional Services teams.

Gateways must report to an FQDN that is shared by the Primary and Secondary AMM servers. Initially, the FQDN should resolve to the Primary server’s IP address. Upon failover, you must update the DNS server to switch the FQDN to the Secondary server’s IP address.

Requirements

For HA failover to operate, you will need two servers with active network connections running AMM-2.17+, and both must have similar system configurations in terms of RAM, disk size, CPU cores, and other hardware features. The two servers must be able to ping their default gateway and also be able to fully communicate with each other. There must be no tampering or restrictions on the traffic between the HA peers. Access to the HA servers must be available to Sierra Wireless Customer Support and Professional Services teams. You must also be licensed for two servers, having purchased either the AM Enterprise or AMM Enterprise server license. The Enterprise Lite license is not sufficient.

For a list of ports required for HA failover see High Availability (HA) Failover Port Summary .

It is highly recommended to keep traffic unrestricted and untouched between the two servers. External packet inspection and active filtering may prevent proper HA setup and will eventually break HA operations. There must be no delay in traffic between the two HA peers.

For additional information contact your Sierra Wireless Partner Regional Sales Manager.