NAME

     fpsync — Synchronize directories in parallel using fpart and an external tool

SYNOPSIS

     fpsync [-p] [-n jobs] [-w wrks] [-m tool] [-T path] [-f files] [-s size] [-E] [-o toolopts]
            [-O fpartopts] [-S] [-t tmpdir] [-d shdir] [-M mailaddr] [-v] src_dir/ dst_url/
     fpsync -l
     fpsync -r runid [-R] [OPTIONS...]
     fpsync -a runid
     fpsync -D runid

DESCRIPTION

     The fpsync tool synchronizes directories in parallel using fpart(1) and rsync(1), cpio(1) or
     tar(1).  It computes subsets of src_dir/ and spawns jobs to synchronize them to dst_url/.

     Synchronization jobs can be executed either locally or remotely (using SSH workers, see
     option -w) and are executed on-the-fly while filesystem crawling goes on.  This makes fpsync
     a good tool for migrating large filesystems.

COMMON OPTIONS

     -t tmpdir
             Set fpsync temporary directory to tmpdir.  This directory remains local and does not
             need to be shared amongst SSH workers when using the -w option.  Default:
             /tmp/fpsync

     -d shdir
             Set fpsync shared directory to shdir.  This option is mandatory when using SSH
             workers and set by default to tmpdir when running locally.  The specified directory
             must be an absolute path ; it will be used to handle communications with SSH hosts
             (sharing partitions and log files) and, as a consequence, must be made available to
             all participating hosts (e.g. through a r/w NFS mount), including the master one
             running fpsync.

     -M mailaddr
             Send an e-mail to mailaddr after a run.  Multiple -space-separated- addresses can be
             specified.  That option requires the mail(1) client to be installed and configured
             on the master host running fpsync.

     -v      Verbose mode.  Can be be specified several times to increase verbosity level.

     -h      Print help

SYNCHRONIZATION OPTIONS

     -m tool
             External copy tool used to synchronize files.  Currently supported tools are: rsync,
             cpio, tar, and tarify.  Default: rsync.  When using cpio or tar and more than one
             worker, directory timestamps may not be replicated.  A second pass will fix them.
             Special tool tarify generates tarballs into destination directory.

     -T path
             Specify absolute path of copy tool (guessed by default).  If you force a specific
             path, the copy tool must be present at that path on each worker.  That path cannot
             be changed when resuming a run.

     -f files
             Transfer at most files files or directories per sync job.  0 means unlimited but you
             must at least specify one file or size limit.  Default: 2000

     -s size
             Transfer at most size bytes per sync job.  0 means unlimited but you must at least
             specify one file or size limit.  You can use a human-friendly unit suffix here (k,
             m, g, t, p).
             Default: 4294967296 (4 GB)

     -E      Work on a per-directory basis (rsync tool only).  In that mode, fpsync works with
             lists of directories instead of files.  That mode may generate coarse-grained lists
             but enables rsync(1) 's --delete option by default ( WARNING!!!  ), making it a good
             candidate for a final (cleaning) pass after several incremental passes using
             standard (file) mode.  When option -E is specified twice, it enables 'aggressive'
             mode which isolates erroneous directories and enables recursive synchronization for
             them.  This advanced mode can be useful to try to overcome transcient errors such as
             Linux SMB client deferring opendir() calls to support compound SMB requests.

     -o toolopts
             Override default rsync(1), cpio(1) or tar(1) options with toolopts.  Use this option
             with care as certain options are incompatible with a parallel usage (e.g. rsync's
             --delete).  Default for rsync: “-lptgoD -v --numeric-ids”.  Empty for cpio, tar and
             tarify.

     -O fpartopts
             Override default fpart(1) options with fpartopts.  Options and values must be
             separated by a pipe character.
             Default: “-x|.zfs|-x|.snapshot*|-x|.ckpt”.

     -S      Sudo mode.  Use sudo(8) for filesystem crawling and synchronizations.

     src_dir/
             Source directory.  It must be absolute and available on all participating hosts
             (including the master one, running fpsync).

     dst_url/
             Destination directory or URL (rsync tool only).  If a remote URL is provided, it
             must be supported by rsync(1).  All participating workers must be able to reach that
             target.

JOB HANDLING AND DISPATCHING OPTIONS

     -n jobs
             Start jobs concurrent sync jobs (either locally or remotely, see below) per run.
             Default: 2

     -w wrks
             Use remote SSH wrks to synchronize files.  Synchronization jobs are executed locally
             when this option is not set.  wrks is a space-separated list of login@machine
             connection strings and can be specified several times.  You must be allowed to
             connect to those machines using a SSH key to avoid user interaction.

RUN HANDLING OPTIONS

     -p      Prepare mode: prepare, test synchronization environment, start fpart(1) and create
             partitions but do not actually start transfers.  That mode can be used to create a
             run that can then be resumed using option -r.

     -l      List previous runs and their status.

     -r runid
             Resume run runid and restart synchronizing remaining partitions from a previous run.
             runid is displayed when using verbose mode (see option -v) or prepare mode (option
             -p) and can be retrieved afterwards using option -l.  Note that filesystem crawling
             is skipped when resuming a previous run.  As a consequence, options -m, -f, -s, -E,
             -o, -O, -S, src_dir/, and dst_url/ are ignored.

     -R      Replay mode: when using option -r, force re-synchronizing run's all partitions
             instead of remaining ones only.  That mode can be useful to skip filesystem crawling
             when you have to replay a final pass several times and you know directory structure
             has not changed in the meantime (you may miss files if you use replay mode with a
             standard, file-based, run).

     -a runid
             Archive run runid (including partition files, logs, queue and work directories) to
             tmpdir.  That option requires the tar(1) client to be installed on the master host
             running fpsync.

     -D runid
             Delete run runid (including partition files, logs, queue and work directories).

RUNNING FPSYNC

     Each fpsync run generates a unique runid, which is displayed in verbose mode (see option -v)
     and within log files.  You can use that runid to resume a previous run (see option -r).
     fpsync will then restart synchronizing data from the parts that were being synchronized at
     the time it stopped.

     This unique feature gives the administrator the ability to stop fpsync and restart it later,
     without having to restart the whole filesystem crawling and synchronization process.  Note
     that resuming is only possible when filesystem crawling step has finished.

     During synchronization, you can press CTRL-C to interrupt the process.  The first CTRL-C
     prevents new synchronizations from being submitted and the process will wait for current
     synchronizations to be finished before exiting.  If you press CTRL-C again, current
     synchronizations will be killed and fpsync will exit immediately.  When using option -E to
     enable directory mode and rsync's --delete option, keep in mind that killing rsync processes
     may lead to a situation where certain files have been updated and others not deleted yet
     (because the deletion process is postponed using rsync's --delete-after option).

     On certain systems, CTRL-T can be pressed to get the status of current and remaining parts
     to be synchronized.  This can also be achieved by sending a SIGINFO to the fpsync process.

     Whether you use verbose mode or not, everything is logged within shdir/log/.

EXAMPLES

     Here are some examples:

     fpsync -n 4 /usr/src/ /var/src/

             Synchronizes /usr/src/ to /var/src/ using 4 local jobs.

     fpsync -n 2 -w login@machine1 -w login@machine2 -d /mnt/fpsync /mnt/src/ /mnt/dst/

             Synchronizes /mnt/src/ to /mnt/dst/ using 2 concurrent jobs executed remotely on 2
             SSH workers (machine1 and machine2).  The shared directory is set to /mnt/fpsync and
             mounted on the machine running fpsync, as well as on machine1 and machine2.  The
             source directory (/mnt/src/) is also available on those 3 machines, while the
             destination directory (/mnt/dst/) is mounted on SSH workers only (machine1 and
             machine2).

LIMITATIONS

     Parallelizing rsync(1) can make several options not usable, such as --delete.  If your
     source directory is live while fpsync is running, you will have to delete extra files from
     destination directory.  This is traditionally done by using a final -offline- rsync(1) pass
     that will use this option, but you can also use fpsync and option -E to perform the same
     task using several workers.

     fpsync enqueues synchronization jobs on disk, within the tmpdir/queue directory.  Be careful
     to host this queue on a filesystem that can handle fine-grained mtime timestamps (i.e. with
     a sub-second precision) if you want the queue to be processed in order when fpart(1)
     generates several jobs per second.  On FreeBSD, VFS(9) timestamps' precision can be tuned
     using the 'vfs.timestamp_precision' sysctl.  See vfs_timestamp(9).

     Contrary to rsync(1), fpsync enforces the final '/' on the source directory.  It means that
     directory contents are synchronized, not the source directory itself (i.e. you will not get
     a subdirectory of the name of the source directory in the target directory after
     synchronization).

     Before starting filesystem crawling, fpsync changes its current working directory to
     src_dir/ and generates partitions containing relative paths (all starting with './').  This
     is important to keep in mind when modifying toolopts or fpartopts dealing with file or
     directory paths.

     If you want to run fpsync in the background, your shell must support enabling job control
     without a tty in non-interactive mode.  As of this writing, Dash does not support that
     feature and will send a SIGTTIN to the whole process group, suspending fpsync execution.

SEE ALSO

     cpio(1), fpart(1), mail(1), rsync(1), tar(1), sudo(8)

AUTHOR, AVAILABILITY

     Fpsync has been written by Ganaël LAPLANCHE and is available under the BSD license on
     http://contribs.martymac.org

BUGS

     No bug known (yet).