Each server contains two internal mirrored disks.
The LSMS is implemented with a pair of redundant servers and the following redundant heartbeat connections between them:
A bonded pair of Ethernet connections for heartbeats
A serial cable connection for heartbeats
Two servers, one active and one standby, provide redundancy in processing. If the active server fails, the LSMS can run on the standby server.
Changing from one server to another is called switchover. The server on which the LSMS is running at a given time is called the active server and the other server is called the standby server.
For some types of failure on the active server, the LSMS automatically attempts to switch over. You can also manually switch over at any time. For more information about switching over, see the following:
The LSMS is designed with the following data redundancies:
Each server contains mirrored disks. If both sides of the mirrors fail on the active server, the LSMS automatically attempts to switch over to the standby server. For more information, see Automatic Switchover Due to Hardware-Related Failure.
The database on the active server is replicated by the standby server.
The servers use heartbeats to monitor each other. The servers are connected by a pair of redundant Ethernet connections and a serial connection. As long as each server is functioning, it sends its heartbeat to the other server over these connections. These two Ethernet connections are implemented on separate Ethernet cards, so that the failure of one Ethernet card does not prevent heartbeats from being sent.
The heartbeats are monitored by the Surveillance feature. If a heartbeat cannot be detected, one of the following notifications is posted:
LSMS4015|14:58 Jun 22, 2000|xxxxxxx|Notify:Sys Admin - Heartbeat 1 failure
LSMS4016|14:58 Jun 22, 2000|xxxxxxx|Notify:Sys Admin - Heartbeat 2 failure