HP VA7410 manual Battery, Early Warning Switch, Disk Drives

Chapter 4

Peripherals and Accessories

In a dual controller configuration, both controllers must have the same amount of cache memory as the contents of NVRAM are mirrored between the two controllers. This mirroring process insures that both controllers have exactly the same information in the event of a failure. The controller battery maintains NVRAM contents when normal power is not present. If the battery fails or loses its charge while power is off, the NVRAM contents are lost on that controller. To protect against data loss, the array power/standby switch turns off power to the array and the “Shutdown Operation” copies NVRAM contents to the disk drives in slots 1 and 2 of the array. This allows reconstruction of the data in NVRAM if the original data is lost or corrupted.

Note: When upgrading a VA7400 to a VA7410 or a VA7100 to a VA7110 or a VA7410, both DIMMs need to be the same part number (A6186-60002, for example).

Note: The process of copying the contents of NVRAM to the two recovery disks makes the disk set independent of its controller. Because all the necessary mapping information is on these disks, it is possible to install a new controller or move the entire disk set to another controller. The new controller will determine that it has a new disk set, and the controller will attach itself to those disks.

DIMM Sizes and Cache Sizes

Array	Minimum Cache	Maximum Cache
VA7100	256-MB/controller	1024-MB/controller
VA7110	1024-MB/controller	2048-MB/controller
VA7410	1024-MB / controller	2048-MB / controller
Configurations of only one size DIMM in controllers are	supported (for example, mixing 512-MB and 1024-MB DIMMs in the same controller is not supported).

Slot 1 DIMM (MB)	Slot 2 DIMM (MB)	Total Memory (MB)	VA7100	VA7110	VA7410
256-MB	–	256-MB	Y	N	N
256-MB	256-MB	512-MB	Y	N	N
512-MB	–	512-MB	Y	N	N
512-MB	512-MB	1024-MB	Y	Y*	Y*
1024-MB	–	1024-MB	Y	Y	Y
1024-MB	1024-MB	2048-MB	N	Y	Y

* This is a supported configuration, but new VA7110 controllers will not ship with 512-MB DIMMs.

Battery

Each array controller includes one battery to supply backup power to the DIMMs in the event have a power failure or if array power is switched off. If power is lost, the BATTERY LED will flash with a 5% duty cycle while it powers the DIMMs. The battery will maintain a charge for 3.5 days. If the battery loses its charge, or if it is removed from the controller, the DIMMs have no power and NVRAM contents are lost. A battery should be replaced when the software indicates a battery has failed.

Early Warning Switch

In a dual controller configuration, the NVRAM contents on both controllers are updated constantly. By maintaining a mirror image of the NVRAM, the secondary controller can take over immediately if the primary controller fails. If a dual controller needs to be replaced online, an early warning switch incorporated into the latch detects when the controller is being removed. Releasing the latch disables communication between controllers before power is lost to the controller being removed. This prevents corruption of the NVRAM contents.

Disk Drives

The array must have a minimum of four disk drives installed. Several types of disk drives can be installed in the array and capacities can be mixed within the array:

•18-GB Low-Profile Fibre Channel 15,000 rpm (supported, but no longer orderable)

•36-GB Low-Profile Fibre Channel 10,000 rpm

•36-GB Low-Profile Fibre Channel 15,000 rpm

•73-GB Low-Profile Fibre Channel 10,000 rpm

•73-GB Low-Profile Fibre Channel 15,000 rpm

•146-GB Low-Profile Fibre Channel 10,000 rpm (VA7410 and VA7110 arrays only)

4-112	HP e3000 Business Servers Configuration Guide – Effective 1/04
	Information Subject to Change