Compaq Infortrend manual Data Safety

Redundant Controller
Communication over	Dedicated loops or distribution over drive loops selectable
Fibre loops
No Single-point-of-	Supported.
failure
Automatic engagement	Supported in PowerPC series
of replacement
controller
Dynamic cache memory	Yes. Cache memory is dynamically allocated, not fixed.
allocation
Environment	Supported. SAF-TE, S.E.S., ISEMS (I2C interface); and
management	on-board controller voltage/temp monitor are all supported
	in both single and redundant controller mode. In the event
	of controller failure, serves can be taken over by the
	existing controller.
Cache battery backup	Supported. Battery backup solutions for cache memory
	are supported in both single controller and redundant
	modes.
Load sharing	Supported. Workload can be flexibly divided between
	different controllers by assigning logical configurations of
	drives (LDs/LVs) to different controllers.
User configurable	Supported. Channel modes configurable (SCSI or Fibre)
channel mode	as HOST or DRIVE in both single controller and redundant
	controller mode.
Require a special	No. All firmware and all Infortrend external RAID
Firmware for redundant	controllers support redundant controller function.
controller?
Redundant Controller	Firmware upgrade can be downloaded to the primary
rolling firmware upgrade	controller and then be adopted by both controllers, without
	interrupting host I/O.
Redundant Controller	In the event of controller failure, a replacement controller
firmware	running a different version of firmware can be combined to
synchronization	restore a redundant system with a failed controller.
	Different firmware versions can be auto-synchronized
	later.

Data Safety:

	Regenerate Parity of	Supported. Can be performed every so often by user to
	logical drives	ensure that bad sectors do not cause data loss in the
		event of drive failure.
	Bad block auto-	Supported.	Automatic reassignment of bad block
	reassignment
	Battery backup for	Supported. The battery backup solutions provide long-
	cache memory	lasting battery support to the cache memory when power
		failure occurs. The unwritten data in the cache memory
		can be committed to drive media when power is restored.
	Verification on Normal	Supported. Performs read-after-write during normal write
	Writes	processes to ensure data is properly written to drives.
	Verification on Rebuild	Supported. Performs read-after-write during rebuild write
	Writes	to ensure data is properly written to drives.
Firmware Functionality Specifications			B-7