ZFS

Revision as of 01:01, 7 November 2021 by David (talk | contribs) (Created page with "How to use ZFS: ==Background== There are three levels to understand * zpools are a JBOD of one or more vdevs * vdevs are groups of drives, likely in raidz(2|3) or mirror. * d...")
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
\( \newcommand{\P}[]{\unicode{xB6}} \newcommand{\AA}[]{\unicode{x212B}} \newcommand{\empty}[]{\emptyset} \newcommand{\O}[]{\emptyset} \newcommand{\Alpha}[]{Α} \newcommand{\Beta}[]{Β} \newcommand{\Epsilon}[]{Ε} \newcommand{\Iota}[]{Ι} \newcommand{\Kappa}[]{Κ} \newcommand{\Rho}[]{Ρ} \newcommand{\Tau}[]{Τ} \newcommand{\Zeta}[]{Ζ} \newcommand{\Mu}[]{\unicode{x039C}} \newcommand{\Chi}[]{Χ} \newcommand{\Eta}[]{\unicode{x0397}} \newcommand{\Nu}[]{\unicode{x039D}} \newcommand{\Omicron}[]{\unicode{x039F}} \DeclareMathOperator{\sgn}{sgn} \def\oiint{\mathop{\vcenter{\mathchoice{\huge\unicode{x222F}\,}{\unicode{x222F}}{\unicode{x222F}}{\unicode{x222F}}}\,}\nolimits} \def\oiiint{\mathop{\vcenter{\mathchoice{\huge\unicode{x2230}\,}{\unicode{x2230}}{\unicode{x2230}}{\unicode{x2230}}}\,}\nolimits} \)

How to use ZFS:

Background

There are three levels to understand

  • zpools are a JBOD of one or more vdevs
  • vdevs are groups of drives, likely in raidz(2|3) or mirror.
  • datasets are filesystems stored on a zpool
  • z

Usage

# Create a zpool with a mirror vdev
zpool create -f -o ashift=12 $zpool_name mirror \
  /dev/disk/by-id/diskA \
  /dev/disk/by-id/diskB

Pros and Cons

VS Snapraid + btrfs + mergerfs

Pros
  • ZFS has realtime parity.
  • ZFS can work while degraded.
  • ZFS snapshots with send and receive.
  • ZFS has encryption on per-dataset.
  • ZFS handles everything altogether including parity on permissions
Cons
  • The main con is that ZFS is less expandable. You need to buy all of your drives up front.
  • If many drives die, i.e. >2 for raidz2, you lose all your data.


Resources