Ubuntu Server Software RAID
Install mdadm
sudo apt install mdadm
List Disks
lsblk -o NAME,SIZE,FSTYPE,TYPE,MOUNTPOINT
example output
NAME SIZE FSTYPE TYPE MOUNTPOINT
xvda 8G disk
└─xvda1 8G ext4 part /
xvdf 3G disk
xvdg 3G disk
xvdh 3G disk
xvdi 3G disk
xvdj 3G disk
xvdk 3G disk
xvdl 3G disk
xvdm 3G disk
List RAID
cat /proc/mdstat
example output (no RAID)
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
unused devices: <none>
Create RAID 0
sudo mdadm --create --verbose {{ raid_device.value }} --level=0 {{ option_raid_devices }}
verify
cat /proc/mdstat
example output (RAID0)
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
md0 : active raid0 xvdm[7] xvdl[6] xvdk[5] xvdj[4] xvdi[3] xvdh[2] xvdg[1] xvdf[0]
25149440 blocks super 1.2 512k chunks
unused devices: <none>
verify again
sudo mdadm --detail {{ raid_device.value }}
example output (RAID0)
/dev/md0:
Version : 1.2
Creation Time : Wed Nov 30 15:26:47 2016
Raid Level : raid0
Array Size : 25149440 (23.98 GiB 25.75 GB)
Raid Devices : 8
Total Devices : 8
Persistence : Superblock is persistent
Update Time : Wed Nov 30 15:26:47 2016
State : clean
Active Devices : 8
Working Devices : 8
Failed Devices : 0
Spare Devices : 0
Chunk Size : 512K
Name : ip-10-0-0-33:0 (local to host ip-10-0-0-33)
UUID : 496c2a3c:65257670:0224b312:07e34442
Events : 0
Number Major Minor RaidDevice State
0 202 80 0 active sync /dev/xvdf
1 202 96 1 active sync /dev/xvdg
2 202 112 2 active sync /dev/xvdh
3 202 128 3 active sync /dev/xvdi
4 202 144 4 active sync /dev/xvdj
5 202 160 5 active sync /dev/xvdk
6 202 176 6 active sync /dev/xvdl
7 202 192 7 active sync /dev/xvdm
Save the RAID Array Layout
sudo mdadm --detail --scan | sudo tee -a /etc/mdadm/mdadm.conf
sudo update-initramfs -u
# manual edit
sudo {{ texteditor.value }} /etc/mdadm/mdadm.conf
Format and Mount RAID
sudo mkfs.ext4 -i 2048 {{ raid_device.value }}
and continue to Ubuntu Server Format Disk and Mount Disk
Remove RAID
sudo mdadm --stop {{ raid_device.value }}
sudo mdadm --remove {{ raid_device.value }}
sudo mdadm --misc --zero-superblock /dev/sdc
sudo mdadm --misc --zero-superblock /dev/sdd
sudo {{ texteditor.value }} /etc/mdadm/mdadm.conf