ZFS Cheatsheet

Create a pool

Get disk ids from /dev/disk/by-id, do not use /dev/sdX
zpool create <name> <type> <disks>
Example: zpool create ssds mirror nvme-Samsung_SSD_980_TB_ABCD nvme-Samsung_SSD_980_TB_EFGH
Don't set ashift, let zfs figure it out. You can check with zdb -C <pool> what value it uses.
- Only set it, if it's wrong. ashift=12 for 4K physical sectors
Set autotrim=on for SSDs
When creating a pool -o is for pool options. To pass options to the root dataset, use -O.

A good set of defaults for a new pool: -o autotrim=on -O acltype=posixacl -O xattr=sa -O normalization=formD -O compression=zstd -O atime=on -O relatime=on

Create a dataset

zfs create <pool>/<dataset>
Disabling atime is no longer necessary, just make sure that both atime and relatime are on
For encryption specify: -o encryption=on -o keyformat=raw -o keylocation=file:///path/to/key
Enable comporession: -o compression=zstd
recordsize of 128K is default. When storing large files, e.g., media, set this higher, e.g., 1M