Unsaved Data In The Controller Cache - Promise Technology VTrack M-Class M200f Product Manual

Chapter 8: Troubleshooting

Unsaved Data in the Controller Cache

The VTrak M-Class controller has a 256 MB data memory cache protected by a
battery backup. If there is a power failure while unsaved data is in the cache, the
battery will power the cache and hold the data up to 72 hours.
Dirty Cache LED (Fibre Channel)
Dirty Cache LED (iSCSI)
Dirty Cache LED (SCSI)
An LED (marked with the icon) is provided to inform you that there is data in
the cache that has not been saved to non-volatile memory. Such data is
sometimes called "dirty," not to suggest it is corrupted in some way but because it
has not been saved to a disk drive.
If a power failure has occurred and there is unsaved data in the controller's
cache, the Dirty Cache LED shines amber. During this time, do NOT remove the
cooling unit (M300f/i/p or M200f/i/p) or the cooling unit with the battery
(M500f/i/p). Wait until power service is restored. After the VTrak reboots
completely, the data will be saved automatically and the LED will go dark.
If you have turned off the power manually, turn the power on again and allow the
VTrak to boot itself completely. Then the data will be saved automatically and the
LED will stop flashing.
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