OVH Setup server hybrid second disk array
As OVH doesn’t provide a guide to install the second disk array, which is sold optionally, I will publish my solution.
Please be careful, only try these on test configurations and without any disks containing critical data. Some commands can destroy all of your data.
There seems to be soon a solution within the manager – but for now this isn’t working:
Tested on Ubuntu 14.04
Some commands to detect your actual configuration:
fdisk -l lsblk -o NAME,SIZE,FSTYPE,TYPE,MOUNTPOINT df -h -x devtmpfs -x tmpfs |
Delete sdb1/sda1 with parted:
parted /dev/sdb (parted) print Model: ATA HGST HUS726040AL (scsi) Disk /dev/sdb: 4001GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags 1 1049kB 537MB 536MB primary boot (parted) rm 1 (parted) quit parted /dev/sda (parted) print Model: ATA HGST HUS726040AL (scsi) Disk /dev/sda: 4001GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags 1 1049kB 537MB 536MB primary boot (parted) rm 1 (parted) quit |
Add new raid partition (needs to be done for sdb and sda):
# Create raid 1 in live linux system parted -a optimal /dev/sdb # Place a flag gpt or mbr mklabel gpt # Create partition mkpart primary ext4 0% 100% # Mark partition as software raid partition set 1 raid on # Verify its alligned align-check optimal # Show results print # Create raid 1 in live linux system parted -a optimal /dev/sda # Place a flag gpt or mbr mklabel gpt # Create partition mkpart primary ext4 0% 100% # Mark partition as software raid partition set 1 raid on # Verify its alligned align-check optimal # Show results print |
Create new raid configuration (‘level’ can be used for RAID0/1/5 …):
mdadm --create --verbose /dev/md4 --level=0 --assume-clean --raid-devices=2 /dev/sdb1 /dev/sda1 cat /proc/mdstat |
In case of renaming:
# Delete all and rescan mdadm -Ss mdadm --assemble --verbose /dev/md4 /dev/sdb1 /dev/sda1 |
Update mdadm configuration:
# NOT NECCESSAIRE MAYBY USEFUL # mdadm --monitor --daemonise /dev/md4 # Capture output mdadm --detail --scan # Something like: 'ARRAY /dev/md4 UUID=7d45838b:7886c766:5802452c:653f8cca' # Needs to be added to the end of file: /etc/mdadm/mdadm.conf # Update initramfs (ignore errors): update-initramfs -v -u # Create file system: mkfs.ext4 -F /dev/md4 # Mount fs: mount /dev/md4 /opt/ # Update fstab: /etc/fstab /dev/md4 /opt ext4 defaults 0 1 |
Could look something like that:
lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sdb 8:16 0 3.7T 0 disk
`-sdb1 8:17 0 3.7T 0 part
`-md4 9:4 0 7.3T 0 raid0 /opt
nvme1n1 259:0 0 419.2G 0 disk
|-nvme1n1p3 259:3 0 5.4G 0 part [SWAP]
|-nvme1n1p1 259:1 0 511M 0 part
`-nvme1n1p2 259:2 0 413.3G 0 part
`-md2 9:2 0 413.3G 0 raid1 /
sda 8:0 0 3.7T 0 disk
`-sda1 8:1 0 3.7T 0 part
`-md4 9:4 0 7.3T 0 raid0 /opt
nvme0n1 259:4 0 419.2G 0 disk
|-nvme0n1p3 259:7 0 5.4G 0 part [SWAP]
|-nvme0n1p1 259:5 0 511M 0 part /boot/efi
`-nvme0n1p2 259:6 0 413.3G 0 part
`-md2 9:2 0 413.3G 0 raid1 / |
Now you can reboot the server and verify your configuration.
https://doc.ubuntu-fr.org/raid_logiciel
https://www.psylogical.org/node/198
https://www.digitalocean.com/community/tutorials/how-to-create-raid-arrays-with-mdadm-on-ubuntu-16-04
https://github.com/etalab/etalab-support/tree/master/procedures
https://docs.ovh.com/fr/dedicated/raid-soft/
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