RAID
Create RAID 5 Ubuntu
Disk Information
lsblk -o NAME,SIZE,FSTYPE,TYPE,MOUNTPOINT
NAME SIZE FSTYPE TYPE MOUNTPOINT sda 931.5G disk └─sda1 931.5G ntfs part /var/lib/transmission-daemon/downloads/HM_30 sdb 931.5G disk └─sdb1 931.5G ntfs part sdc 931.5G disk └─sdc1 931.5G ntfs part /var/lib/transmission-daemon/downloads/HM_40 sdd 931.5G disk ├─sdd1 100M ntfs part ├─sdd2 293G ntfs part ├─sdd3 14G ntfs part ├─sdd4 1K part ├─sdd5 28G ext4 part / ├─sdd6 93.1G ext4 part /home ├─sdd7 11.2G swap part [SWAP] └─sdd8 1.9G ext4 part /var/log sdi 3.7T disk sdj 3.7T disk sdk 3.7T disk sdl 3.7T disk sr0 1024M rom
blkid
/dev/sdh: UUID="45dcb1c7-5dcd-8d8e-7830-0cdc8da5755c" UUID_SUB="c52532c2-fa0b-e5f2-9a71-166b20d63084" LABEL="Morpheus:0" TYPE="linux_raid_member" /dev/sdj: UUID="45dcb1c7-5dcd-8d8e-7830-0cdc8da5755c" UUID_SUB="524b7cad-dd3d-cd84-2f4b-228f691fb660" LABEL="Morpheus:0" TYPE="linux_raid_member" /dev/sdk: UUID="45dcb1c7-5dcd-8d8e-7830-0cdc8da5755c" UUID_SUB="f7105152-6eb2-3f7c-28a2-61f0f8c966d8" LABEL="Morpheus:0" TYPE="linux_raid_member" /dev/sdl: UUID="45dcb1c7-5dcd-8d8e-7830-0cdc8da5755c" UUID_SUB="a7dad691-d287-f1e2-17e2-76cbdd543b27" LABEL="Morpheus:0" TYPE="linux_raid_member"
Create RAID 5
sudo mdadm --create --verbose /dev/md0 --level=5 --raid-devices=4 /dev/sdi /dev/sdj /dev/sdk /dev/sdl
Monitor the array progress creation with
cat /proc/mdstat
Output:
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
md0 : active raid5 sdl[4] sdk[2] sdj[1] sdi[0]
11720658432 blocks super 1.2 level 5, 512k chunk, algorithm 2 [4/3] [UUU_]
[>....................] recovery = 0.0% (2091700/3906886144) finish=7753.1min speed=8393K/sec
bitmap: 0/30 pages [0KB], 65536KB chunk
unused devices: <none>
Save the array layout
Wait until the array creation is finished and run:
sudo mdadm --detail --scan | sudo tee -a /etc/mdadm/mdadm.conf
Enable the array at boot time
sudo update-initramfs -u
Using LVM
pvcreate /dev/md0 vgcreate lvm_group_name /dev/md0 lvcreate -L30G -nlogical_volume_group_name lvm_group_name mkfs.ext4 /dev/lvm_group_name/logical_volume_group_name echo '/dev/lvm_group_name/logical_volume_group_name /mnt/mountdir ext4 defaults,nofail,discard 0 0' | sudo tee -a /etc/fstab
Using EXT4
Create the filesystem
sudo mkfs.ext4 -F /dev/md0
Mount the filesystem
sudo mount /dev/md0 /mnt/md0
Add mount option to fstab
echo '/dev/md0 /mnt/md0 ext4 defaults,nofail,discard 0 0' | sudo tee -a /etc/fstab
TODO: Add a disk to RAID5 with LVM
https://ubuntuforums.org/showthread.php?t=713936
LVM and RAID Cheatsheet
Check RAID status
mdadm -D /dev/md0
References
https://www.digitalocean.com/community/tutorials/how-to-create-raid-arrays-with-mdadm-on-ubuntu-16-04#top
https://unix.stackexchange.com/questions/88654/what-does-mdadms-spare-number-mean
https://wiki.bandaancha.st/RAID_y_LVM_en_Linux
https://zackreed.me/software-raid-5-in-debian-with-mdadm/
https://zackreed.me/adding-an-extra-disk-to-an-mdadm-array/