Setting up an Ubuntu 22.04 Server with RAID1 and LVM

Voici toutes les étapes nécessaires à la construction d'un RAID1 logiciel sur Ubuntu 22.
Source

Création du RAID logiciel

Although setting up a simple single-drive Ubuntu server is a good start for building your self-hosted cloud, adding a second drive as a RAID array to the system from the start will give you far improved reliability and a greater sense of security for your data. Even if you have a drive fail, you have a redundant mirrored drive to keep your data safe and operational until you can replace the failed drive.

Additionally, LVM affords you the ability to somewhat future-proof your storage by essentially creating a virtual disk that you can migrate between physical disks and expand without needing to worry about the underlying storage configuration being a limiting factor.

Here's how to set up a RAID1 mirrored system with LVM from the start.

I dismiss simple easy first steps

Under Guided storage configuration, select Custom storage layout and hit the space bar
Select Done and hit enter
Storage configuration
Clear all partitions from your drives (if existing partitions/RAID exist)

You should now have 2 identically-sized drives with all free space under AVAILABLE DEVICES

For each of your drives under AVAILABLE DEVICES :

Tab to select the local disk and hit enter
Tab to select Use As Boot Device (or Add As Another Boot Device) and hit enter
Tab- to select free space under that drive and hit enter
Tab- to select Add GPT Partition and hit enter
Tab, then hit enter
Tab to select Leave unformatted, then hit enter
Tab to select Create then hit enter
Select Create software RAID (md) and hit enter
Leave Name as md0 and tab
Leave RAID Level as 1 (mirrored) and tab
Tab to the first of you drives' partitions labeled as partition 2 and hit Space to choose it
Tab to the second of you drives' partitions labeled as partition 2 and hit Space to choose it
Tab to Create and hit enter
Under md0 select free space and hit enter
Select Add GPT Partition and hit enter
Set the Size to 2G and hit tab
Tab again, leaving Format set to ext4
On Mount, hit enter, then select /boot, then hit enter
Tab to select Create then hit enter
Under md0 select free space again and hit enter
Select Add GPT Partition and hit enter
Leave the Size blank and hit tab
Hit enter on Format, select Leave unformatted, and hit enter
Tab to select Create then hit enter
Select Create volume group (LVM) and hit enter
Leave Name set to vg0 and hit tab
Under md0 select partition 2 and hit space to choose it
Tab to Create and hit enter
Under vg0 (new) select free space and hit enter
Select Create Logical Volume and hit enter
Leave the Name set to lv-0
Select Create and hit enter
Select Done and hit enter
On the Confirm destructive action screen, select Continue and hit enter

Congrats! You made it past the most complicated part of the installation!

Extension du volume pour qu'il utilise l'intégralité du volume

Il arrive que le volume logique (VL) créé n'utilise pas tout l'espace disponible dans le volume group (VG). Pour s'en assurer, utiliser les commandes vgdisplay pour obtenir les infos du VG et lvdisplay pour le VL.
Si LV Size est inférieur à VG Size, utiliser la commande suivante pour étendre le volume logique :

lvextend -l +100%FREE /dev/ubuntu-vg/ubuntu-lv

Reste à redimensionner le système de fichier avec la commande suivante :

resize2fs /dev/ubuntu-vg/ubuntu-lv

Check of RAID construction

Here are some commands in order to check RAID existence and replication :

cat /proc/mdstat

Sample output :

  md0 : active raid1 nvme1n1p2[1] nvme0n1[0]  
975526912 blocks super 1.2 [2/2] [UU]  
bitmap: 4/8 pages [16KB], 65536KB chunk

`sudo mdadm --detail /dev/md0`

Sample output :

/dev/md0:  
           Version : 1.2  
     Creation Time : Tue Feb 20 08:27:49 2024  
        Raid Level : raid1  
        Array Size : 975526912 (930.33 GiB 998.94 GB)  
     Used Dev Size : 975526912 (930.33 GiB 998.94 GB)  
      Raid Devices : 2  
     Total Devices : 2  
       Persistence : Superblock is persistent  

     Intent Bitmap : Internal  

       Update Time : Tue Feb 20 12:18:55 2024  
             State : clean  
    Active Devices : 2  
   Working Devices : 2  
    Failed Devices : 0  
     Spare Devices : 0  

Consistency Policy : bitmap  

              Name : ubuntu-server:0  
              UUID : a1a4a38d:bbda50c1:0316aea9:6c666b28  
            Events : 1876  

    Number   Major   Minor   RaidDevice State  
       0     259        0        0      active sync   /dev/nvme0n1  
       1     259        3        1      active sync   /dev/nvme1n1p2

`watch cat /proc/mdstat`

Permet de suivre en direct la réplication des disques