HowTo: ZFS on Proxmox — pool, snapshots and replication

ZFS gives you instant snapshots, checksums (integrity), compression and replication — ideal for 1-2 nodes. Step-by-step setup on Proxmox.

1. Create the pool

# pool ZFS in mirror (2 discuri) — ashift=12 pt discuri 4K
zpool create -o ashift=12 tank mirror /dev/sdb /dev/sdc
# sau raidz1 (3 discuri, toleranta 1 disc):
# zpool create -o ashift=12 tank raidz1 /dev/sdb /dev/sdc /dev/sdd
zpool status

2. Tuning + dataset

zfs set compression=lz4 tank      # compresie rapida, aproape gratis
zfs set atime=off tank            # mai putine scrieri
zfs create tank/vmdata            # dataset dedicat pt VM-uri

3. Add to Proxmox

# in Proxmox: Datacenter -> Storage -> Add -> ZFS -> pool 'tank/vmdata'
# (discurile VM ajung ca zvol-uri, cu snapshots instant)
pvesm status

4. Snapshots

# snapshot instant + listare + rollback
zfs snapshot tank/vmdata@inainte-update
zfs list -t snapshot
zfs rollback tank/vmdata@inainte-update

5. Node-to-node replication

# replicare programata catre alt nod (Proxmox pve-zsync / Replication)
# GUI: VM -> Replication -> Add -> nod tinta + interval
# CLI echivalent:
pvesr create-local-job 100-0 pve2 --schedule '*/15'

6. Limit ARC (RAM)

# ZFS foloseste RAM pt cache (ARC). Limiteaza pe hosturi cu putin RAM:
echo 'options zfs zfs_arc_max=8589934592' > /etc/modprobe.d/zfs.conf  # 8 GiB
update-initramfs -u && reboot

Conclusion

You now have storage with snapshots, integrity and replication, no external array. NOTE: ZFS wants raw disks (HBA), not hardware RAID. We size it for you.