ZSD(1) User Contributed Perl Documentation ZSD(1)NAMEzsd - Quickly destroys a specified amount of ZFS snapshots
SYNOPSISzsd [--gather-snapshots-sorted-by-name] [--fork-and-forget]
[--verbose][--verbose] --keep number-of-snapshots --destroy number-of-
snapshots [--not-really] dataset
zsd [--gather-snapshots-sorted-by-name] [--fork-and-forget]
[--verbose][--verbose] --keep number-of-snapshots [--not-really]
dataset
zsd [--gather-snapshots-sorted-by-name] [--fork-and-forget]
[--verbose][--verbose] --destroy number-of-snapshots [--not-really]
dataset
zsd--help
DESCRIPTIONzsd (ZFS snapshot destroyer) is a zfs(8) wrapper to destroy a number of
snapshots on a given dataset using a more convenient interface.
The number of snapshots to destroy can be specified directly, or
indirectly by specifying the number of snapshots that should be kept.
Snapshots are destroyed in the (by default chronological) order they
are listed by zfs list.
zsd goes nicely with zogftw's zogftw_snapshot_successfully_sent_hook to
grow a certain number of snapshots on new backup datasets while keeping
the number of snapshots on old backup datasets constant.
zsd is mainly developed and tested using OpenZFS on FreeBSD, but is
expected to work on other platforms as well.
OPTIONS--destroy number-of-snapshots If enough snapshots are available,
destroy snapshots until reaching either the specified number or the
number of snapshots to keep specified with --keep. If --keep isn't
used, one snapshot is kept so receival of incremental snapshots
continues to work.
--gather-snapshots-sorted-by-name Let zfs(8) list the available
snapshots sorted by name which is a lot faster (on FreeBSD) as less
metadata has to be read. This should only be used if the order in which
snapshots are destroyed doesn't matter or if sorting the snapshots by
name keeps the chronological order.
--fork-and-forget Fork a process for each snapshots that should be
destroyed and don't check if the operation is successful. If the ZFS
pool feature async_destroy is unsupported or disabled, this is
generally faster than destroying the snapshots one-by-one. The
downside is that it requires more memory and that errors are ignored.
Destroying too many snapshots at the same time can cause some FreeBSD
versions to become unresponsive under some conditions and rebooting the
system a couple of times may take longer than destroying the snapshots
one-by-one. You may want to experiment with this option before using it
in production environments.
--keep number-of-snapshots When used without --destroy and if enough
snapshots are available, snapshots are destroyed until the given number
of snapshots is reached. If the option is used together with --destroy,
it specifies the number of snapshots that should be kept.
--not-really Show how many snapshots would be destroyed if the option
wasn't being used, but don't actually destroy them.
--verbose Be more verbose. When specified once, the destroyed snapshots
are shown. When specified twice, the kept snapshots are shown as well.
All options can be shortened as long as there are no ambiguities.
EXAMPLES
The following examples are independent and assume a dataset
tank/blafasel with 100 snapshots.
zsd--destroy 10 tank/blafasel Destroys 10 snapshots.
zsd--destroy 100 tank/blafasel Destroys 99 snapshots as not using
--keep implies that at least one snapshot should be kept.
zsd--destroy 100 --keep 0 tank/blafasel Destroys all the 100 snapshots
as no snapshot has to be kept.
zsd-d 100 -k 0 tank/blafasel Same as the above, but requires less
typing.
zsd--destroy 100 --keep 40 tank/blafasel Destroys 60 snapshots as 40
snapshots have to be kept.
zsd--destroy 10 --keep 40 tank/blafasel Destroys 10 snapshots, keeping
90 as 40 is only the lower limit.
zsd-d 20 -k 20 -n tank/blafasel Shows how many snapshots would be
destroyed without -n.
zsd--destroy 100 --keep 200 tank/blafasel Destroys no snapshot as the
number of snapshots to keep is above the number of snapshots available
on the dataset.
zsd--keep 10 tank/blafasel Destroys 90 snapshots as not using
--destroy implies that all the snapshots above the limit should be
destroyed.
SEE ALSOzfs(8)zogftw(8)zpool-features(7)AUTHOR
Fabian Keil <fk@fabiankeil.de>
perl v5.14.4 2014-09-09 ZSD(1)
