Ubuntu Manpage: mfssnapshots - MooseFS snapshot tools

Provided by: moosefs-client_4.57.5-1_amd64

NAME

       mfssnapshots - MooseFS snapshot tools

SYNOPSIS

       mfsappendchunks [-?] [-s FROM:TO] SNAPSHOT_FILE FILE...

       mfsmakesnapshot [-?] [-o|-c|-p] SOURCE_OBJECT... DESTINATION

       mfsrmsnapshot [-?] [-f] OBJECT...

DESCRIPTION

mfsappendchunks (equivalent of mfssnapshot from MooseFS 1.5) appends a lazy copy of specified FILE(s) to
specified SNAPSHOT_FILE ("lazy" means that creation of new chunks is delayed to the moment one copy is
modified). IF SNAPSHOT_FILE does not exist, it is created. If multiple files are given, they are merged
into one target file in such a way that each file begins at chunk (64MB) boundary; padding space is left
empty. Optionally only slice of chunks can be appended (option -s). Slice definition is similar to
Python: FROM is included, TO excluded, negative numbers mean backwards from the end. If FROM or TO is not
specified then it means from the beginning or to the end of file respectively. See examples below.

mfsmakesnapshot makes a "real" snapshot (lazy copy, like in case of mfsappendchunks) of some object(s) or
subtree (similarly to cp -r command). It's atomic with respect to each SOURCE_OBJECT argument separately.
If DESTINATION points to already existing file, error will be reported unless -o (overwrite) option is
given. If destination points to an already existing directory, snapshot is created inside this directory.
Note: if SOURCE_OBJECT is a directory, it is copied as a whole; but if it's followed by trailing slash,
only directory content is copied. When -c option is given then attributes of newly created files are more
similar to those created by ordinary cp (without attribute preserving). Option -p preserves hardlinks in
SOURCE (when two or more objects inside SOURCE are hardlinked to each other then in DESTINATION folder
those objects will be hardlinked to each other as well).

mfsrmsnapshot removes objects created as a result of mfsmakesnapshot (similarly to rm -r, but much
faster). For safety reasons objects created via mfsmakesnapshot have the snapshot attribute set (see
mfseattr(1)) and only such objects can be removed using mfsrmsnapshot command. By default all files and
directories inside specified directory must have this attribute set for the command to remove the whole
directory; otherwise the command will not remove anything. This behavior can be overridden by -f option.
With this option mfsrmsnapshot will remove only those files/directories that have snapshot attribute set
and will leave everything else untouched.

SLICES

       FROM:TO for source file with chunks 0,1,2,...,N-1,N:

       2:4 = chunks 2 and 3

       3: = chunks 3,4,...,N

       :5 = chunks 0,1,2,3,4

       :-1 = chunks 0,1,2,3,...,N-1

       -4:-2 = chunks N-3,N-2

GENERAL OPTIONS

       Option -? displays short usage message.

REPORTING BUGS

       Report bugs to <bugs@moosefs.com>.

COPYRIGHT

       Copyright (C) 2025 Jakub Kruszona-Zawadzki, Saglabs SA

       This file is part of MooseFS.

       MooseFS is free software; you can redistribute it and/or modify it under the terms  of  the  GNU  General
       Public License as published by the Free Software Foundation, version 2 (only).

       MooseFS  is  distributed  in  the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the
       implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR  PURPOSE.  See  the  GNU  General  Public
       License for more details.

       You  should  have  received a copy of the GNU General Public License along with MooseFS; if not, write to
       the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,  MA  02111-1301,  USA  or  visit
       http://www.gnu.org/licenses/gpl-2.0.html