Compaq HSZ80 manual 28General Description

1–28General Description

	Table 1–9	Resulting Cache Policies and ECB Status (Continued)
Cache Module Status		Cache Policy
Cache A	Cache B	Unmirrored Cache	Mirrored Cache
Failed	Less than	Data loss: No.	Data loss: No.
	50%	Cache policy: Both controllers	Cache policy: Both controllers support
	charged
		support write-through caching only.	write-through caching only.
		Failover: In transparent failover, all	Failover: No.
		units failover to controller B and
		operate normally.
		In multiple-bus failover with host-
		assist, only those units that use
		write-back caching, such as
		RAIDsets and mirrorsets, failover to
		controller B.
		In single-controller configurations,
		the controller only provides write-
		through caching to its units.
Failed	Failed	Data loss: No.	Data loss: No.
		Cache policy: Both controllers	Cache policy: Both controllers support
		support write-through caching only.	write-through caching only.
		Failover: No. RAIDsets and mirrorsets	Failover: No. RAIDsets and mirrorsets
		become inoperative. Other units that	become inoperative. Other units that
		use write-back caching operate with	use write-back caching operate with
		write-through caching only.	write-through caching only.