-.TH lfs_migrate 1 "Jul 21, 2010" Lustre "utilities"
+.TH lfs_migrate 1 "Jun 16, 2017" Lustre "utilities"
.SH NAME
-.Blfs_migrate
+.B lfs_migrate
\- simple tool to migrate files between Lustre OSTs
.SH SYNOPSIS
.B lfs_migrate
.RB [ -c <stripe_count> ]
.RB [ -h ]
-.RB [ -l ]
.RB [ -n ]
.RB [ -q ]
.RB [ -R ]
.RB [ -s ]
+.RB [ -S <stripe_size> ]
.RB [ -y ]
+.RB [ -0 ]
.RI [ file | "directory ..." ]
.br
.SH DESCRIPTION
is simply copying each specified file to a new file, verifying the file
contents have not changed, and then renaming the new file back to the
original filename. This allows balancing space usage between OSTs, moving
-files of OSTs that are starting to show hardware problems (though are still
-functional), or OSTs will be discontinued.
+files off OSTs that are starting to show hardware problems (though are still
+functional), or OSTs that will be removed from the filesystem.
.PP
Because
.B lfs_migrate
is
.B not
-closely integrated with the MDS, it cannot determine whether a file
+yet closely integrated with the MDS, it cannot determine whether a file
is currently open and/or in-use by other applications or nodes. That makes
it
.B
.B \\-h
Display help information.
.TP
-.B \\-l
-Migrate files with hard links (skip by default). Files with multiple
-hard links will be split into multiple separate files by
-.B lfs_migrate
-so they are skipped by default to avoid breaking the hard links.
-.TP
.B \\-n
-Only print the names of files to be migrated
+Only print the names of files to be migrated.
.TP
.B \\-q
-Run quietly (don't print filenames or status)
+Run quietly (don't print filenames or status).
.TP
.B \\-R
Restripe file using default directory striping instead of keeping striping.
-This option may not be specified at the same time as the -c option.
+This option may not be specified at the same time as the -c or -S options.
.TP
.B \\-s
-skip file data comparison after migrate. Default is to compare migrated file
+Skip file data comparison after migrate. Default is to compare migrated file
against original to verify correctness.
.TP
+.B \\-S <stripe_size>
+Restripe file using the specified stripe size. This option may not be
+specified at the same time as the -R option.
+.TP
.B \\-y
Answer 'y' to usage warning without prompting (for scripts, use with caution).
+.TP
+.B \\-0
+Input file names on stdin are separated by a null character.
.SH EXAMPLES
To rebalance all files within
-.IR /mnt/lustre/dir :
+.I /testfs/jobs/2011
+(which are known not to be modified by in-use programs):
.IP
-lfs_migrate /mnt/lustre/dir
+lfs_migrate /testfs/jobs/2011
.PP
To migrate files within the
-.I /test
-filesystem on OST0004 larger than 4GB in size:
+.I /testfs
+filesystem on OST0004 (perhaps because it is much more full than other OSTs),
+larger than 4GB (because it is more efficient to just migrate large files),
+and older than two days (to avoid files that are in use, though this is NOT
+a guarantee the files are not being modified, that is workload specific):
.IP
-lfs find /test -obd test-OST0004 -size +4G | lfs_migrate -y
+lfs find /testfs -obd test-OST0004 -size +4G -mtime +2d |
+ lfs_migrate -y
.SH KNOWN BUGS
-Hard links could be handled correctly in Lustre 2.0 by using
-.BR lfs (1) " fid2path" .
-.PP
Eventually, this functionality will be integrated into
.BR lfs (1)
itself and will integrate with the MDS layout locking to make it safe
in the presence of opened files and ongoing file IO.
-.PP
-Please report all bugs to http://bugzilla.lustre.org/
.SH AVAILABILITY
.B lfs_migrate
is part of the
git://git.whamcloud.com / fs / lustre-release.git / blobdiff