This article shows how to create a 3 SATA DISK RAID5 confgiuration using Oracle Enterprise Linux 5.5 aka Redhat 5.5.
I used a small 40GB drive the boot drive. This could have been anything including another Mirror but I didn’t go that nuts with my failover. I just wanted to make sure that if one of my primary DATA disks went bad, I would be able to recover with just buying another 54 dollar TB drive.
- Load OEL 5.5 on 40GB IDE or SATA drive.
- fdisk each of the SATA drives setting the format type to “fd”
Command (m for help): nCommand action e extended p primary partition (1-4)pPartition number (1-4): 1First cylinder (1-121601, default 1): Using default value 1Last cylinder or +size or +sizeM or +sizeK (1-121601, default 121601): Using default value 121601
Command (m for help): p
Disk /dev/sdc: 1000.2 GB, 1000204886016 bytes255 heads, 63 sectors/track, 121601 cylindersUnits = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System/dev/sdc1 1 121601 976760001 83 Linux
Command (m for help): tSelected partition 1Hex code (type L to list codes): fdChanged system type of partition 1 to fd (Linux raid autodetect)
Command (m for help): wThe partition table has been altered!
- Then run the following mdadm command line to create RAID 5 array
mdadm –create –verbose /dev/md0 –level=5 –raid-devices=3 /dev/sda1 /dev/sdb1 /dev/sdc1
- Check your work to make sure the configuration is enabled.
- Next make your filesystem on /dev/md0
- The configuration of your raid is unfortunately not saved until you run the following:
- Create your mount point directory
- Edit your /etc/fstab to include the following:
/dev/md0 /mnt/DATA ext3 defaults 1 2
- mount your new 3 TB (now only 1.9 TB) drive.
mount -a