2.3 Failure detection by HA Monitor
When a failure occurs in a system that uses HA Monitor, HA Monitor detects the failure. HA Monitor then performs the hot standby operation if it is able to do so. If hot standby is not possible, HA Monitor does not perform it.
Both server failures and host failures can occur in the system. The failure detection method depends on the failure type. This section explains how failures are detected for each failure type. It also explains the conditions under which HA Monitor performs the hot standby operation and the methods used to achieve hot standby, including the mechanism of host reset, SCSI reservation, and the function for controlling hot standby based on the availability of LAN communications.