Commit Graph

11 Commits

Author SHA1 Message Date
Richard Laager 6bf3f4dfe5 Fix a dependency loop
When generating units with zfs-mount-generator, if the pool is already
imported, zfs-import.target is not needed.  This avoids a dependency
loop on root-on-ZFS systems:
  systemd-random-seed.service After (via RequiresMountsFor)
  var-lib.mount After
  zfs-import.target After
  zfs-import-{cache,scan}.service After
  cryptsetup.service After
  systemd-random-seed.service

Reviewed-by: Antonio Russo <antonio.e.russo@gmail.com>
Reviewed-by: InsanePrawn <insane.prawny@gmail.com>
Signed-off-by: Richard Laager <rlaager@wiktel.com>
Closes #10388
2020-08-30 14:18:41 -07:00
Jonathon f1de1600d1
Verify zfs module loaded before starting services
This is a minor change to the systemd service templates that verifies
the zfs kernel module is loaded by the kernel prior to attempting to
import any zpool.

The services check for the presence of /sys/module/zfs which indicates
the zfs is module is loaded. This uses the systemd built-in check
ConditionPathIsDirectory.

Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Thode <prometheanfire@gentoo.org>
Signed-off-by: Jonathon Fernyhough <jonathon.fernyhough@york.ac.uk>
Closes #10663
2020-08-01 17:13:15 -07:00
Jonathon ae12b02308
Verify zfs module loaded before starting services
This is a minor change to the systemd service templates that verifies the zfs
kernel module is loaded by the kernel prior to attempting to import any zpool.

Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Jonathon Fernyhough <jonathon.fernyhough@york.ac.uk>
Closes #10627
2020-07-29 16:52:18 -07:00
Didier Roche 8ae8b2a144 Workaround to avoid a race when /var/lib is a persistent dataset
If /var/lib is a dataset not under <pool>/ROOT/<root_dataset>, as
proposed in the ubuntu root on zfs upstream guide
(https://github.com/zfsonlinux/zfs/wiki/Ubuntu-18.04-Root-on-ZFS),
we end up with a race where some services, like systemd-random-seed
are writing under /var/lib, while zfs-mount is called. zfs mount will
then potentially fail because of /var/lib isn't empty and so, can't be
mounted.
Order those 2 units for now (more may be needed) as we can't declare
virtually a provide mount point to match
"RequiresMountsFor=/var/lib/systemd/random-seed" from
systemd-random-seed.service.
The optional generator for zfs 0.8 fixes it, but it's not enabled
by default nor necessarily required.

Example:
- rpool/ROOT/ubuntu (mountpoint = /)
- rpool/var/ (mountpoint = /var)
- rpool/var/lib  (mountpoint = /var/lib)

Both zfs-mount.service and systemd-random-seed.service are starting
After=systemd-remount-fs.service. zfs-mount.service should be done
before local-fs.target while systemd-random-seed.service should finish
before sysinit.target (which is a later target).
Ideally, we would have a way for zfs mount -a unit to declare all paths
or move systemd-random-seed after local-fs.target.

Reviewed-by: Antonio Russo <antonio.e.russo@gmail.com>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Didier Roche <didrocks@ubuntu.com>
Closes #9360
2019-10-02 10:51:55 -07:00
Antonio Russo 80b485246a Cleanup systemd dependencies
Some redundancy is present in the systemd dependencies, as
noticed in PR#6764. Existing setups might rely on these quirks,
so these cleanups have been moved to the development branch.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Antonio Russo <antonio.e.russo@gmail.com>
Closes #6822
2017-11-08 09:39:15 -08:00
Antonio Russo 5c2552c564 systemd zfs-import.target and documentation
zfs-import-{cache,scan}.service must complete before any mounting of
filesystems can occur. To simplify this dependency, create a target
that is reached After (in the systemd sense) the pool is imported.

Additionally, recommend that legacy zfs mounts use the option

x-systemd.requires=zfs-import.target

to codify this requirement.

Reviewed-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Signed-off-by: Antonio Russo <antonio.e.russo@gmail.com>
Closes #6764
2017-10-30 13:18:26 -07:00
Fabian-Gruenbichler c8811dec70 Add man page reference to systemd units
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Closes #6599
2017-09-05 13:50:35 -07:00
LOLi 9000a9fac9 Disable mount(8) canonical paths in do_mount()
By default the mount(8) command, as invoked by 'zfs mount', will try
to resolve any path parameter in its canonical form: this could lead
to mount failures when the cwd contains a symlink having the same name
of the dataset being mounted.

Fix this by explicitly disabling mount(8) path canonicalization.

Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes #1791 
Closes #6429 
Closes #6437
2017-08-21 09:31:54 -07:00
Brian Behlendorf d32d25c5c2 Fix zfs-mount.service failure on boot
The mount(8) command will helpfully try to resolve any device name
which is passed in.  It does this by applying some simple heuristics
before passing it along to the registered mount helper.

Normally this fine.  However, one of these heuristics is to prepend
the current working directory to the passed device name.  If that
resulting directory name exists mount(8) will perform the mount(2)
system call and never invoke the helper utility.

Since the cwd for systemd when running as the system instance is
the root directory the default mount points created by zfs(8) can
cause a mount failure.

This change avoids the issue by explicitly setting the cwd to
a different path when performing the mount.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #5719
2017-02-08 10:17:29 -08:00
Brian Behlendorf 92547bc45c Systemd configuration fixes
* Disable zfs-import-scan.service by default.  This ensures that
pools will not be automatically imported unless they appear in
the cache file.  When this service is explicitly enabled pools
will be imported with the "cachefile=none" property set.  This
prevents the creation of, or update to, an existing cache file.

    $ systemctl list-unit-files | grep zfs
    zfs-import-cache.service                  enabled
    zfs-import-scan.service                   disabled
    zfs-mount.service                         enabled
    zfs-share.service                         enabled
    zfs-zed.service                           enabled
    zfs.target                                enabled

* Change services to dynamic from static by adding an [Install]
section and adding 'WantedBy' tags in favor of 'Requires' tags.
This allows for easier customization of the boot behavior.

* Start the zfs-import-cache.service after the root pivot so
the cache file is available in the standard location.

* Start the zfs-mount.service after the systemd-remount-fs.service
to ensure the root fs is writeable and the ZFS filesystems can
create their mount points.

* Change the default behavior to only load the ZFS kernel modules
in zfs-import-*.service or when blkid(8) detects a pool.  Users
who wish to unconditionally load the kernel modules must uncomment
the list of modules in /lib/modules-load.d/zfs.conf.

Reviewed-by: Richard Laager <rlaager@wiktel.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4325
Closes #4496
Closes #4658
Closes #4699
2016-05-27 11:54:29 -07:00
Ralf Ertzinger 881f45c6a8 Add systemd unit files for ZFS startup
This adds systemd unit files replacing the functionality offered by
the SysV init script found in etc/init.d.

It has been developed and tested on Fedora 19, Fedora 20
and openSuSE 13.1.

Four unit files and one target are offered.

zfs-import-cache.service:
    Import pools from /etc/zfs/zpool.cache. This unit will wait for
    udev to settle.
zfs-import-scan.service:
    Import pools by scanning /dev/disk/by-id for zvols. This unit will
    only run if /etc/zfs/zpool.cache is not present. This unit will wait
    for udev to settle
zfs-mount.service:
    Mount ZFS native filesystems. It contains a dependency to be loaded
    before local-fs.target.
zfs-share.service:
    Share NFS/SMB filesystems. This unit contains a dependency that
    will cause it to be restarted whenever the smb or nfs-server unit
    is restarted, restoring the shares added.
zfs.target:
    This target pulls in the other units in order to start ZFS. It's
    the only unit that can be enabled/disabled, all other services
    are static and pulled in by dependencies. It will honour zfs=off
    and zfs=no options on the kernel command line.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2108
2014-02-05 12:25:30 -08:00