vfs_shadow_copy2
8
Samba
System Administration tools
4.1
vfs_shadow_copy2
Expose snapshots to Windows clients as shadow copies.
vfs objects = shadow_copy2
DESCRIPTION
This VFS module is part of the
samba
7 suite.
The vfs_shadow_copy2 VFS module functionality
that is similar to Microsoft Shadow Copy services. When setup properly,
this module allows Microsoft Shadow Copy clients to browse
"shadow copies" on Samba shares.
This is a 2nd implementation of a shadow copy module. This
version has the following features:
You don't need to populate your shares with symlinks to the
snapshots. This can be very important when you have thousands of
shares, or use [homes].
The inode number of the files is altered so it is different
from the original. This allows the 'restore' button to work
without a sharing violation.
This module is stackable.
CONFIGURATION
vfs_shadow_copy2 relies on a filesystem
snapshot implementation. Many common filesystems have native
support for this.
Filesystem snapshots must be mounted on
specially named directories in order to be recognized by
vfs_shadow_copy2. The snapshot mount points must
be immediate children of a the directory being shared.
The snapshot naming convention is @GMT-YYYY.MM.DD-hh.mm.ss,
where:
YYYY is the 4 digit year
MM is the 2 digit month
DD is the 2 digit day
hh is the 2 digit hour
mm is the 2 digit minute
ss is the 2 digit second.
The vfs_shadow_copy2 snapshot naming convention can be
produced with the following date
1 command:
TZ=GMT date +@GMT-%Y.%m.%d-%H.%M.%S
OPTIONS
shadow:snapdir = SNAPDIR
Path to the directory where snapshots are kept.
shadow:basedir = BASEDIR
Path to the base directory that snapshots are from.
shadow:sort = asc/desc, or not specified for unsorted (default)
By this parameter one can specify that the shadow
copy directories should be sorted before they are sent to the
client. This can be beneficial as unix filesystems are usually
not listed alphabetically sorted. If enabled, you typically
want to specify descending order.
shadow:localtime = yes/no
This is an optional parameter that indicates whether the
snapshot names are in UTC/GMT or in local time. By default
UTC is expected.
shadow:format = format specification for snapshot names
This is an optional parameter that specifies the format
specification for the naming of snapshots. The format must
be compatible with the conversion specifications recognized
by str[fp]time. The default value is "@GMT-%Y.%m.%d-%H.%M.%S".
shadow:fixinodes = yes/no
If you enable shadow:fixinodes
then this module will modify the apparent inode
number of files in the snapshot directories using a hash of the
files path. This is needed for snapshot systems where the
snapshots have the same device:inode number as the original
files (such as happens with GPFS snapshots). If you don't set
this option then the 'restore' button in the shadow copy UI
will fail with a sharing violation.
shadow:snapdirseverywhere = yes/no
If you enable
shadow:snapdirseverywhere then this module will look
out for snapshot directories in the current and all parent
directories of the current working directory.
An example where this is needed are independent filesets in
IBM's GPFS, but other filesystems might support snapshotting
only particular subtrees of the filesystem as well.
EXAMPLES
Add shadow copy support to user home directories:
shadow_copy2
/data/snapshots
/data/home
desc
CAVEATS
This is not a backup, archival, or version control solution.
With Samba or Windows servers,
vfs_shadow_copy2 is designed to be an end-user
tool only. It does not replace or enhance your backup and
archival solutions and should in no way be considered as
such. Additionally, if you need version control, implement a
version control system.
VERSION
This man page is correct for version 3.2.7 of the Samba suite.
AUTHOR
The original Samba software and related utilities
were created by Andrew Tridgell. Samba is now developed
by the Samba Team as an Open Source project similar
to the way the Linux kernel is developed.