NAME

       zfs-mount-generator - generates systemd mount units for ZFS

SYNOPSIS

       /usr/lib/systemd/system-generators/zfs-mount-generator

DESCRIPTION

       zfs-mount-generator  implements  the  Generators  Specification of systemd(1), and is called during early
       boot  to  generate  systemd.mount(5)  units  for  automatically  mounted  datasets.  Mount  ordering  and
       dependencies are created for all tracked pools (see below).

   ENCRYPTION KEYS
       If  the  dataset  is  an  encryption  root,  a service that loads the associated key (either from file or
       through a systemd-ask-password(1) prompt) will be created. This service RequiresMountsFor the path of the
       key (if file-based) and also copies the mount unit's After, Before and Additionally, unless  the  logical
       flag  is  set,  the  mount  unit  gains a reverse-dependency for of strength Because ZFS pools may not be
       available very early in the boot process, information on ZFS mountpoints must be stored  separately.  The
       output of the command

           zfs                              list                              -H                              -o
           name,mountpoint,canmount,atime,relatime,devices,exec,readonly,setuid,nbmand,encroot,keylocation,org.openzfs.systemd:requires,org.openzfs.systemd:requires-
           mounts-for,org.openzfs.systemd:before,org.openzfs.systemd:after,org.openzfs.systemd:wanted-
           by,org.openzfs.systemd:required-by,org.openzfs.systemd:nofail,org.openzfs.systemd:ignore

       for datasets that should be mounted by systemd, should be kept separate from the pool, at

           /etc/zfs/zfs-list.cache/POOLNAME

       The cache file, if writeable, will be kept synchronized with the pool state by the ZEDLET

           history_event-zfs-list-cacher.sh .

   PROPERTIES
       The behavior of the generator script can be influenced by the following dataset properties:

       canmount=on|off|noauto
           If a dataset has  mountpoint  set  and  canmount  is  not  off,  a  mount  unit  will  be  generated.
           Additionally, if canmount is on, local-fs.target will gain a dependency on the mount unit.

           This behavior is equal to the auto and noauto legacy mount options, see systemd.mount(5).

           Encryption roots always generate a key-load service, even for canmount=off.

       org.openzfs.systemd:requires-mounts-for=path...
           Space-separated list of mountpoints to require to be mounted for this mount unit

       org.openzfs.systemd:before=unit...
           The  mount  unit  and associated key-load service will be ordered before this space-separated list of
           units.

       org.openzfs.systemd:after=unit...
           The mount unit and associated key-load service will be ordered after  this  space-separated  list  of
           units.

       org.openzfs.systemd:wanted-by=unit...
           Space-separated  list  of  units  that will gain a Wants dependency on this mount unit.  Setting this
           property implies noauto.

       org.openzfs.systemd:required-by=unit...
           Space-separated list of units that will gain a Requires dependency on this mount unit.  Setting  this
           property implies noauto.

       org.openzfs.systemd:nofail=unset|on|off
           Toggles  between  a Wants and Requires type of dependency between the mount unit and local-fs.target,
           if noauto isn't set or implied.

           on: Mount will be WantedBy local-fs.target

           off: Mount will be Before and RequiredBy local-fs.target

           unset: Mount will be Before and WantedBy local-fs.target

       org.openzfs.systemd:ignore=on|off
           If set to on, do not generate a mount unit for this dataset.

           See also systemd.mount(5)

EXAMPLE

       To begin, enable tracking for the pool:

           touch /etc/zfs/zfs-list.cache/POOLNAME

       Then, enable the tracking ZEDLET:

           ln -s "/usr/lib/zfs-linux/zed.d/history_event-zfs-list-cacher.sh" "/etc/zfs/zed.d"

           systemctl enable zfs-zed.service

           systemctl restart zfs-zed.service

       Force the running of the ZEDLET by setting a monitored property, e.g.  canmount, for at least one dataset
       in the pool:

           zfs set canmount=on DATASET

       This forces an update to the stale cache file.

       To test the generator output, run

           /usr/lib/systemd/system-generators/zfs-mount-generator /tmp/zfs-mount-generator . .

       This will generate units and dependencies in /tmp/zfs-mount-generator for you to inspect them. The second
       and third argument are ignored.

       If you're satisfied with the generated units, instruct systemd to re-run all generators:

           systemctl daemon-reload

SEE ALSO

       zfs(5) zfs-events(5) zed(8) zpool(5) systemd(1) systemd.target(5) systemd.special(7) systemd.mount(7)

OpenZFS                                           Aug 24, 2020                            ZFS-MOUNT-GENERATOR(8)