Ok, it’s with LVM partitions and 3 disks on RAID1
mount
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime,hidepid=invisible)
udev on /dev type devtmpfs (rw,nosuid,relatime,size=16360116k,nr_inodes=4090029,mode=755,inode64)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,nodev,noexec,relatime,size=3276276k,mode=755,inode64)
/dev/md1 on / type ext4 (rw,relatime)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev,inode64)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k,inode64)
cgroup2 on /sys/fs/cgroup type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
bpf on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime,mode=700)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=31,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=15408)
mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime)
tracefs on /sys/kernel/tracing type tracefs (rw,nosuid,nodev,noexec,relatime)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime,pagesize=2M)
debugfs on /sys/kernel/debug type debugfs (rw,nosuid,nodev,noexec,relatime)
configfs on /sys/kernel/config type configfs (rw,nosuid,nodev,noexec,relatime)
ramfs on /run/credentials/systemd-sysctl.service type ramfs (ro,nosuid,nodev,noexec,relatime,mode=700)
fusectl on /sys/fs/fuse/connections type fusectl (rw,nosuid,nodev,noexec,relatime)
ramfs on /run/credentials/systemd-sysusers.service type ramfs (ro,nosuid,nodev,noexec,relatime,mode=700)
ramfs on /run/credentials/systemd-tmpfiles-setup-dev.service type ramfs (ro,nosuid,nodev,noexec,relatime,mode=700)
/dev/mapper/vg-CRYPTPAD on /mnt/pad type ext4 (rw,relatime)
/dev/mapper/vg-APPS on /mnt/apps type ext4 (rw,relatime)
/dev/mapper/vg-data on /mnt/media type ext4 (rw,relatime)
/dev/mapper/vg-CRYPTPAD on /var/www/cryptpad type ext4 (rw,relatime)
/dev/mapper/vg-CRYPTPAD on /var/www/etherpad_mypads type ext4 (rw,relatime)
/dev/mapper/vg-APPS on /home/yunohost.app/mattermost type ext4 (rw,relatime)
/dev/mapper/vg-APPS on /home/yunohost.app/mobilizon type ext4 (rw,relatime)
/dev/mapper/vg-data on /home/yunohost.app/nextcloud type ext4 (rw,relatime)
/dev/mapper/vg-backups on /mnt/backups type ext4 (rw,relatime)
/dev/mapper/vg-mail on /var/mail type ext4 (rw,relatime)
/dev/mapper/vg-backups on /home/yunohost.backup/archives type ext4 (rw,relatime)
ramfs on /run/credentials/systemd-tmpfiles-setup.service type ramfs (ro,nosuid,nodev,noexec,relatime,mode=700)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,nosuid,nodev,noexec,relatime)
tmpfs on /run/user/25131 type tmpfs (rw,nosuid,nodev,relatime,size=3276272k,nr_inodes=819068,mode=700,uid=25131,gid=25131,inode64)
cat /etc/fstab
UUID=84123fb9-bde8-41dd-a9fc-afd4fe57b0e6 / ext4 defaults 0 1
# partition apps mattermost mobilizon
UUID=cc55dbd0-1abc-411a-a7aa-8a4f6d5eaf50 /mnt/apps ext4 defaults,nofail 0 0
/mnt/apps/mobilizon /home/yunohost.app/mobilizon none defaults,bind 0 0
/mnt/apps/mattermost /home/yunohost.app/mattermost none defaults,bind 0 0
# partition backups borg__2
UUID=86131a6e-ed0d-4071-aa81-41b50e8d3a50 /mnt/backups ext4 defaults,nofail 0 0
/mnt/backups/archives /home/yunohost.backup/archives none defaults,bind 0 0
# partition avec data nextcloud
UUID=4a5b5a94-88ea-4328-a05b-4a3fae339ed2 /mnt/media ext4 defaults,nofail 0 0
/mnt/media/nextcloud /home/yunohost.app/nextcloud none defaults,bind 0 0
# partition mails
UUID=d0294479-075c-480b-972e-0131fef47a5d /var/mail ext4 defaults 0 1
# partition apps cryptpad et etherpad_mypads libreto
UUID=983ea66d-4732-431a-9d31-86eb85bb9431 /mnt/pad ext4 defaults,nofail 0 0
/mnt/pad/cryptpad /var/www/cryptpad none defaults,bind 0 0
/mnt/pad/etherpad_mypads /var/www/etherpad_mypads none defaults,bind 0 0
#/mnt/pad/libreto /var/www/libreto none defaults,bind 0 0
# partition swap
UUID=7ed24519-ae94-459b-acff-af6b12a72c2a swap swap defaults 0 0
UUID=37dc28a5-c4ab-4260-bd4f-d9006f40cfaa swap swap defaults 0 0
UUID=f0ccd1dd-4592-43ac-85de-ee1c149dd688 swap swap defaults 0 0
lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINTS
sda 8:0 0 1.8T 0 disk
├─sda1 8:1 0 68.4G 0 part
│ └─md1 9:1 0 68.3G 0 raid1 /
├─sda2 8:2 0 2G 0 part [SWAP]
├─sda3 8:3 0 1.8T 0 part
│ └─md3 9:3 0 1.8T 0 raid1
│ ├─vg-mail 253:0 0 195.3G 0 lvm /var/mail
│ ├─vg-data 253:1 0 293G 0 lvm /home/yunohost.app/nextcloud
│ │ /mnt/media
│ ├─vg-CRYPTPAD 253:2 0 97.7G 0 lvm /var/www/etherpad_mypads
│ │ /var/www/cryptpad
│ │ /mnt/pad
│ ├─vg-APPS 253:3 0 293G 0 lvm /home/yunohost.app/mobilizon
│ │ /home/yunohost.app/mattermost
│ │ /mnt/apps
│ └─vg-backups 253:4 0 913.7G 0 lvm /home/yunohost.backup/archives
│ /mnt/backups
├─sda4 8:4 0 1K 0 part
└─sda5 8:5 0 1.9M 0 part
sdb 8:16 1 1.8T 0 disk
├─sdb1 8:17 1 68.4G 0 part
│ └─md1 9:1 0 68.3G 0 raid1 /
├─sdb2 8:18 1 2G 0 part [SWAP]
└─sdb3 8:19 1 1.8T 0 part
└─md3 9:3 0 1.8T 0 raid1
├─vg-mail 253:0 0 195.3G 0 lvm /var/mail
├─vg-data 253:1 0 293G 0 lvm /home/yunohost.app/nextcloud
│ /mnt/media
├─vg-CRYPTPAD 253:2 0 97.7G 0 lvm /var/www/etherpad_mypads
│ /var/www/cryptpad
│ /mnt/pad
├─vg-APPS 253:3 0 293G 0 lvm /home/yunohost.app/mobilizon
│ /home/yunohost.app/mattermost
│ /mnt/apps
└─vg-backups 253:4 0 913.7G 0 lvm /home/yunohost.backup/archives
/mnt/backups
sdc 8:32 0 1.8T 0 disk
├─sdc1 8:33 0 68.4G 0 part
│ └─md1 9:1 0 68.3G 0 raid1 /
├─sdc2 8:34 0 2G 0 part [SWAP]
└─sdc3 8:35 0 1.8T 0 part
└─md3 9:3 0 1.8T 0 raid1
├─vg-mail 253:0 0 195.3G 0 lvm /var/mail
├─vg-data 253:1 0 293G 0 lvm /home/yunohost.app/nextcloud
│ /mnt/media
├─vg-CRYPTPAD 253:2 0 97.7G 0 lvm /var/www/etherpad_mypads
│ /var/www/cryptpad
│ /mnt/pad
├─vg-APPS 253:3 0 293G 0 lvm /home/yunohost.app/mobilizon
│ /home/yunohost.app/mattermost
│ /mnt/apps
└─vg-backups 253:4 0 913.7G 0 lvm /home/yunohost.backup/archives
/mnt/backups