HWraid for GNU/Linux

Setting cache on RAID controller

Real RAID controllers (not those found onboard of mainboards) normally have a battery backed cache (or an ultracapacitor + flash memory "zero maintenance cache") which is used for buffering writes to improve speed. Even if it's battery backed, the individual hard disk write caches need to be turned off, as they are not protected from a powerfail and will just lose all contents in that case.

MegaCli Common Commands and Procedures


General Parameters

Adapter parameter -aN

The parameter -aN (where N is a number starting with zero or the string ALL) specifies the adapter ID. If you have only one controller it’s safe to use ALL instead of a specific ID, but you’re encouraged to use the ID for everything that makes changes to your RAID configuration.

Physical drive parameter -PhysDrv [E:S]

User tags

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