csync2(1) cluster synchronization tool, 2nd generation


csync2 [-v..] [-C config-name] [-D database-dir] [-N hostname] [-p port]...


csync2 is copyright © 2004 - 2013 by LINBIT Information Technologies GmbH

csync2 is distributed under the GNU public license. See the file COPYING for details.


This manual page documents briefly the csync2 command.
A verbose manual can be found on the csync2 homepage:

csync2 is a program for cluster wide file synchronization.


With file parameters:

-h [-r] file..
Add (recursive) hints for check to db
-c [-r] file..
Check files and maybe add to dirty db
-u [-d] [-r] file..
Updates files if listed in dirty db
-o [-r] file..
Create list of files in compare-mode
-f [-r] file..
Force files to win next conflict resolution
-m file..
Mark files in database as dirty

Simple mode:

-x [-d] [[-r] file..]
Run checks for all given files and update remote hosts.

Without file parameters:

Check all hints in db and eventually mark files as dirty
-u [-d] Update (transfer dirty files to peers and mark as clear)
List all pending hints from status db
List all file-entries from status db
List all dirty files from status db
-S myname peername
List file-entries from status db for this synchronization pair.
Test if everything is in sync with all peers.
-T filename
Test if this file is in sync with all peers.
-T myname peername
Test if this synchronization pair is in sync.
-T myname peer file
Test only this file in this sync pair.
As -T, but print the unified diffs.
The modes -H, -L, -M and -S return 2 if the requested db is empty. The mode -T returns 2 if both hosts are in sync.
Run in inetd server mode.
Run in stand-alone server mode.
Run in stand-alone server mode (one connect only).
Remove files from database which do not match config entries.

Exit codes:

The modes -H, -L, -M and -S return 2 if the requested db is empty. The mode -T returns 2 if both hosts are in sync. Otherwise, only exit codes 0 (no errors) and 1 (some unspecified errrors) are expected.


Recursive operation over subdirectories
Dry-run on all remote update operations
Do not block everything into big SQL transactions. This slows down csync2 but allows multiple csync2 processes to access the database at the same time. Use e.g. when slow lines are used or huge files are transferred.
Open database in asynchronous mode. This will cause data corruption if the operating system crashes or the computer loses power.
Init-run. Use with care and read the documentation first! You usually do not need this option unless you are initializing groups with really large file lists.
Also add removals to dirty db when doing a -TI run.
Don't mark all other peers as dirty when doing a -TI run.
-G Group1,Group2,Group3,...
Only use these groups from config-file.
-P peer1,peer1,...
Only update these peers (still mark all as dirty). Only show files for these peers in -o (compare) mode.
Add new entries to dirty database with force flag set.
Print timestamps to debug output (e.g. for profiling).
-s filename
Print timestamps also to this file.
-W fd
Write a list of directories in which relevant files can be found to the specified file descriptor (when doing a -c run). The directory names in this output are zero-terminated.

Database switches:

-D database-dir or url
default: /var/lib/csync2
    Absolute path: use sqlite database in that directory.
If database is not given, it defaults to csync2_<qualified hostname>
Note that for non-sqlite backends, the database name is "cleaned", characters outside of [0-9][a-z][A-Z] will be replaced with _.

Creating key file:

csync2 -k filename

Environment variables:

Directory containing csync2.cfg and other csync2 system files. Defaults to /etc.


Csync2 will refuse to do anything if this file is found: $CSYNC2_SYSTEM_DIR/csync2.lock