RAID

Redundant Array of Inexpensive Disks

Links

• http://en.wikipedia.org/wiki/RAID
• Linux Software Raid
• Raid Calculator
• LSI raid level migrations
• https://kb.open-e.com/information-on-configuring-for-optimal-raid-performance_1323.html

• raid failure calculator

ACHTUNG don't forget block/partition alignment!

 

Cache settings

• Difference between write back and write through

HOWTO

Remove raid metadata from disk

DISK=/dev/sdc
# the last bit
dd if=/dev/zero of=$DISK bs=512 seek=$(( $(blockdev --getsz $DISK) - 1024 )) count=1024
# the first bit
dd if=/dev/zero of=$DISK bs=512 count=1

FAQ

Raid levels

RAID 0

stripe

RAID 1

mirror

BBU

Relative State of Charge

Should be well above 90%