You can operate the system switchover facility in either the monitor mode or the server mode. In the monitor mode, only system failures are monitored. In the server mode, both system failures and server failures are monitored. In addition, system switchover can take less time in the server mode than in the monitor mode. Table 8-1 indicates the functional differences between the monitor mode and the server mode.

Table 8-1 Functional differences between the monitor mode and the server mode

Item or function		Monitor mode	Server mode
Monitored failure	System failure1	Y	Y
	Server failure2	N	Y
Functions provided to system switchover time	User server hot standby3	N	Y
	Rapid system switchover facility3	N	Y
Standby-less system switchover facility	Standby-less system switchover (1:1) facility	N	Y
	Standby-less system switchover (effects distributed) facility	N	Y

Legend:

Y: Item is monitored, or the function can be used.

N: Item is not monitored, or the function cannot be used.

¹ In this table, the following failures are assumed to be system failures; however, system failure conditions differ depending on the cluster software used. We recommend you to check your cluster software documentation to verify.

• Hardware failure
• OS failure
• Power outage
• Cluster software failure
• System slowdown

² In this table, the following failures are assumed to be server failures; however, server failure conditions differ depending on the cluster software used. We recommend you to check your cluster software documentation to verify.

• Abnormal termination of HiRDB (or unit if HiRDB/Parallel Server)
• Slowdown of HiRDB (or unit if HiRDB/Parallel Server)
• Database path errors

³ Functions that reduce the system switchover time. For details about user server hot standby and the rapid system switchover facility, see 8.1.5 Functions that reduce system switchover time (user server hot standby and the rapid system switchover facility).

Table 8-2 lists the products you need to operate the system switchover facility in the server mode.

Table 8-2 Products needed to operate in the server mode

Function	HiRDB Advanced High Availability	Hitachi HA Toolkit Extension
Server mode		Y
User server hot standby		Y
Rapid system switchover facility		Y
Standby-less system switchover (1:1) facility	Y	Y
Standby-less system switchover (effects distributed) facility	Y	Y

Legend:

Y: The indicated product is needed to use the facility.

: Not required.

As of the publication date, Hitachi HA Toolkit Extension runs on Windows 2000 Advanced Server only, which means that this functionality can be used only in a Windows 2000 Advanced Server environment.