MONITOMONITORR.\" Sorry for my English .\" --Dmitry Yu Okunev 0x8E30679C .\" .\" Thanks to oldlaptop [https://github.com/oldlaptop] for help with spelling .\" .TH CLSYNC 1 "APRIL 2020" Linux "User Manuals" .de URL \\$2 \(laURL: \\$1 \(ra\\$3 .. .if \n[.g] .mso www.tmac .SH NAME clsync \- live sync tool, written in GNU C .SH SYNOPSIS .B clsync [ ... ] \-\- [ sync\-handler\-arguments ] .SH DESCRIPTION .B clsync executes .I sync\-handler with appropriate arguments on FS events in directory .I watch\-dir using the .BR inotify (7) or other FS monitoring subsystems. .SH OPTIONS This options can be passed as arguments or to be used in the configuration file. To disable numeric option set to zero: .RS =0 .RE To disable string option (for example path to file) set to empty string: .RS = .RE Also you can use previously set values while setting new options. Substring .IR %option_name% will be substituted with previously set value of option .IR option_name . (see .BR "CONFIGURATION FILE" ) .I sync\-handler\-arguments applies only to modes: .RS simple, direct, shell, rsyncdirect, rsyncshell .RE To set .I sync\-handler\-arguments in config file use '\-\-'. An example: .RS \-\- = \-aH \-\-exclude\-from %EXCLUDE\-LIST% \-\-include\-from=%INCLUDE\-LIST% \-\-exclude '*' %watch\-dir%/ %destination\-dir%/ .RE .B \-W, \-\-watch\-dir .I watch\-dir .RS Root directory to be monitored by .BR clsync . Required. .PP .RE .B \-S, \-\-sync\-handler .I sync\-handler .RS Path to .I sync\-handler to be used for syncing by .BR clsync . (see .IR \-\-mode ) Is required for all modes except "direct" and "rsyncdirect" [see .BR "SYNC HANDLER MODES" ] .PP .RE .B \-R, \-\-rules\-file .I rules\-file .RS Path to file with filter rules of objects to be monitored. (see .BR RULES ) Is not set by default. .PP .RE .B \-D, \-\-destination\-dir .I destination\-directory .RS Defines directory to sync to for modes "rsyncdirect", "rsyncso" and "so". (see .IR \-\-mode ) Is not set by default. .PP .RE .B \-M, \-\-mode .I mode .RS Sets syncing mode. Possible values: .RS .IR simple .RS calls .IR sync\-handler " for every event" .RE .IR direct .RS calls .IR sync\-handler " for every sync" with passing files lists as arguments .RE .IR shell .RS calls .IR sync\-handler " for every sync" with passing files lists in a file .RE .IR rsyncdirect .RS calls rsync by path .IR sync\-handler " directly" .RE .IR rsyncshell .RS calls .IR sync\-handler " that supposed to run rsync for every sync (recommended mode)" .RE .IR rsyncso .RS loads shared object by path .IR sync\-handler " with " .BR dlopen "(3) and calls function " clsyncapi_rsync " function for every sync" .RE .IR so .RS loads shared object by path .IR sync\-handler " with " .BR dlopen "(3) and calls function " clsyncapi_sync " function for every sync" .RE .RE See .B SYNC HANDLER MODES .PP Required. .RE .B \-b, \-\-background .RS Daemonize, forcing clsync to fork() on start. Is not set by default. .PP .RE .B \-H, \-\-config\-file .I config\-file\-path .RS Use configuration from file .IR config\-file\-path (see .BR "CONFIGURATION FILE" ). Set to "/NULL/" if no config files should be read. Is not set by default. .PP .RE .B \-K, \-\-config\-block .I config\-block\-name .RS Use configuration block with name .IR config\-block\-name (see .BR "CONFIGURATION FILE" ). The default value is "default". .PP .RE .B \-\-config\-block\-inherits .I config\-parent\-block\-name .RS Use configuration block with name .IR config\-parent\-block\-name as parent for .IR config\-block\-name (see .BR "CONFIGURATION FILE" ). Options from .IR config\-parent\-block\-name will be inherited to .IR config\-block\-name . The default value is "default". .PP .RE .B \-\-custom\-signals .I custom\-signals .RS Set a list of signals and corresponding config block names. The config block will be use on catching the corresponding signal. Format is .RS .I signal:config\-block\-name[,signal:config\-block\-name[,...]] .RE For example: .RS \-\-custom\-signals=29:debug,28:normal .RE In this line signals "28" and "29" will be added to the sighandler. And clsync will use options from config block "debug" on signal 29 and "normal" on signal 28. To reset all custom signals use the 0-th signal (e.g. "\-\-custom\-signals=0"). The default value is "". .PP .RE .B \-z, \-\-pid\-file .I path\-to\-pidfile .RS Writes pid to file by path .IR path\-to\-pidfile . Is not set by default. .PP .RE .B \-\-status\-file .I status\-file\-path .RS Write status description into file with path .IR status\-file\-path . Possible statuses: .RS .IR starting .RS initializing subsystems and marking file tree with FS monitor subsystem .RE .IR initsync .RS processing initial syncing .RE .IR running .RS waiting for events or syncing .RE .IR "synchandler error" .RS waiting between synchandler execution tries (after a failure) [is used only while .BR \-\-threading =off] .RE .IR rehashing .RS reloading configuration files .RE .IR "thread gc" .RS running threads' garbage collector .RE .IR preexit .RS executing the .I \-\-pre\-exit\-hook .RE .IR terminating .RS running the last iteration (if required) and preparing to die .RE .IR exiting .RS executing the .I \-\-exit\-hook and cleaning up [for .BR valgrind (1)] .RE .RE Is not set by default. .PP .RE .B \-r, \-\-retries .I "number-of-tries" .RS Tries limit to sync with .IR sync-handler . .B clsync will die after .I number-of-tries tries. To try infinite set "0". Delay between tries is equal to .I \-\-delay\-sync value. The default value is "1". .RE .B \-\-ignore\-failures .RS Don't die on sync failures. Is not set by default. .RE .B \-\-exit\-on\-sync\-skip .RS Exit if some event could be skipped due to any reason. For example FreeBSD has a very short BSM event queue (1024). So it may be overflowed and some events can not climb to the queue. This option forces .B clsync to exit if the queue had been overflowed. Is not set by default. .RE .B \-p, \-\-threading .I threading-mode .RS .B [Not available on Debian/kFreeBSD] Use .BR pthreads (7) to parallelize syncing processes. For example if .B clsync (with .BR \-\-threading=off ) is already syncing a huge file then all other syncs will be suspended until the huge file syncing finish. To prevent this suspends you can use "safe" or "full" threading mode. Possbile values: .RS .IR off .RS disable threading for syncing processes. .RE .IR safe .RS parallelize syncs but suspend syncings of object that are already syncing in another process (until the process finish). .RE .IR full .RS parallelize syncs without suspendings. .RE .RE Characteristics: .RS .IR off .RS New modifications won't be synced until old ones finish. .RE .IR safe .RS Theoretically is the best way. But may utilize of lot of CPU if there's a lot of simultaneous parallel syncs. (also this way is not well tested) .RE .IR full .RS May cause multiple simultaneous syncing of the same file, which in turn can cause bug inside .IR sync\-handler " (see below)." .RE .RE If you're running .B clsync with option .B \-\-threading=full in conjunction with .B rsync with option .BR \-\-backup , you may catch a bug due to nonatomicity of rsync's file replace operation. (see .BR DIAGNOSTICS ) The default value is "off". .RE .B \-Y, \-\-output .I log\-destination .RS Sets destination for log writing (errors, warnings, infos and debugging). Possible values: .RS .I stderr .br .I stdout .br .I syslog .RE The default value is "stderr". .RE .B \-\-one\-file\-system .RS Don't follow to different devices' mount points. This option just adds option "FTS_XDEV" for .BR fts_open (3) function. .B Warning! If you're using this option (but no \-\-exclude\-mount\-points) .B clsync will write neither includes nor excludes of content of mount points. .br This may cause problems e.g. you're using rsync for sync-handler without similar option "\-\-one\-file\-system". Is not set by default. .RE .B \-X, \-\-exclude\-mount\-points .RS Forces .I \-\-one\-file\-system but also add excludes to do not sync mount points. This requires to do .BR stat (2) syscalls on every dir and can reduce performance. Is not set by default. .RE .B \-\-socket .I socket\-path .RS Create a control socket by path .IR socket\-path . This's very experimental feature. Is not set by default. .RE .B \-\-socket\-own .I socket\-owner\-user[:socket\-owner\-group] .RS Sets the control socket owner user (and group). Is not set by default .RE .B \-\-socket\-mod .I socket\-mode .RS Sets the control socket mode [see .BR chmod (2)]. Is not set by default. .RE .\" .B \-c, \-\-cluster\-iface .\" .I interface\-ip .\" .RS .\" .B Not implemented, yet. .\" .\" .B DANGEROUS OPTION. This functionality wasn't tested well. You can lost your data. .\" .\" Enables inter-node notifing subsystem to prevent sync looping between nodes. .\" This's very useful features that provides ability of birectional sync of the .\" same directory between two or more nodes. .\" .I interface-ip .\" is an IP-address already assigned to the interface that will be used for .\" multicast notifing. .\" .\" Not enabled by default. .\" .\" To find out the IP-address on interface "eth0", you can use for example next .\" command: .\" .\" ip a s eth0 | awk '{if($1=="inet") {gsub("/.*", "", $2); print $2}}' .\" .\" Is not set by default. .\" .RE .\" .\" .PP .\" .B \-m, \-\-cluster\-ip .\" .I multicast\-ip .\" .RS .\" .B Not implemented yet. .\" .\" Sets IP-address for multicast group. .\" .\" This option can be used only in conjunction with .\" .BR \-\-cluster\-interface . .\" .\" Use IP-addresses from 224.0.0.0/4 for this option. .\" .\" The default value is "227.108.115.121". [(128+"c")."l"."s"."y"] .\" .RE .\" .\" .PP .\" .B \-P, \-\-cluster\-port .\" .I multicast\-port .\" .RS .\" .B Not implemented yet. .\" .\" Sets UDP-port number for multicast messages. .\" .\" This option can be used only in conjunction with .\" .BR \-\-cluster\-interface . .\" .\" .I multicast\-port .\" should be greater than 0 and less than 65535. .\" .\" The default value is "40079". [("n" << 8) + "c"] .\" .RE .\" .\" .PP .\" .B \-W, \-\-cluster\-timeout .\" .I cluster\-timeout .\" .RS .\" .B Not implemented yet. .\" .\" Sets timeout (in milliseconds) of waiting answer from another nodes of the .\" cluster. If there's no answer from some node, it will be excluded. .\" .\" The default value is "1000". [1 second] .\" .RE .\" .\" .PP .\" .B \-n, \-\-cluster\-node\-name .\" .I cluster\-node\-name .\" .RS .\" .B Not implemented yet. .\" .\" Sets the name of this node in the cluster. It will be used in action .\" scripts of another nodes (see .\" .BR "SYNC HANDLER MODES" ). .\" .\" The default value is $(uname \-n). .\" .RE .\" .\" .PP .\" .B \-n, \-\-cluster\-node\-id .\" .I cluster\-node\-id .\" .RS .\" .B Not implemented yet. .\" .\" Sets an ID for this node in the cluster. It's used for messaging between .\" cluster nodes. .\" .\" Use value "-1" to choose it automatically. .\" .\" The default value is "-1". .\" .RE .\" .\" .PP .\" .B \-o, \-\-cluster\-hash\-dl\-min .\" .I hash\-dirlevel\-min .\" .RS .\" Sets minimal directory level for ctime hashing (see .\" .BR CLUSTERING ). .\" .\" The default value is "1". .\" .RE .\" .\" .PP .\" .B \-O, \-\-cluster\-hash\-dl\-max .\" .I hash\-dirlevel\-max .\" .RS .\" .B Not implemented yet. .\" .\" Sets maximal directory level for ctime hashing (see .\" .BR CLUSTERING ). .\" .\" The default value is "16". .\" .RE .\" .\" .PP .\" .B \-\-cluster\-scan\-dl\-max .\" .I scan\-dirlevel\-max .\" .RS .\" .B Not implemented yet. .\" .\" Sets maximal directory level for ctime scanning (see .\" .BR CLUSTERING ). .\" .\" The default value is "32". .\" .RE .PP .B \-\-standby\-file .I standby\-file\-path .RS Sets file to path that should be checked before every sync. If file exists the sync will be suspended until the file is deleted. It may be useful if you need freeze destination directory while running some scripts. Is not set by default. .RE .PP .B \-\-max\-iterations .I iterations\-count .RS Sets synchronization iterations limit. One iteration means one sync-handler execution. .I iterations\-count .RS set to 0 means no limit (infinite loop). set to 1 means that only initial sync will be done set to n means that only initial sync and (n-1) sync-ups after that will be done .RE Hint: This option may be useful in conjunction with \-\-exit\-on\-no\-events to prevent infinite sync-up processes. The default value is "0". .RE .B \-\-modification\-signature .I signature\-mask .RS Sets file/dir modification recheck signature. If file is not modified (according to the signature) then don't sync it. See .I "struct stat" in .BR lstat (2) for possible fields. For example reasonable .IR signature\-mask \-s can be "dev,ino,mode,uid,gid,rdev,size,atime,mtime,ctime" (there's an alias for that — "*") or "uid,gid". Examples of use cases: .RS .B chown/chmod .RS If you're using clsync for fixing file/dir privileges [using .BR chown (1) and/or .BR chmod (1)] than reasonable signature will be "uid,gid". Full example: clsync \-w5 \-t5 \-T5 \-x1 \-W /var/www/site.example.org/root \-Mdirect \-Schown \-\-uid 0 \-\-gid 0 \-Ysyslog \-b1 \-\-modification\-signature uid,gid \-\- \-\-from=root www\-data:www\-data %INCLUDE\-LIST% .RE .B "bi\-directional syncing" .RS If you're going to setup bi\-directional syncing then you may use \-\-modification\-signature "*" to prevent sync loop between servers. .RE .B Not enough CPU .RS If rsync eats too many CPU with rechecking hashsums of files on their dry open()/close() due to some hacky script (for example "chown \-R www-data:www-data" in cron) then you can use \-\-modification\-signature "dev,ino,mode,uid,gid,rdev,size,atime,mtime" (without "blksize", "blocks", "nlink" and "ctime"). .RE .RE .B Warning! This option may eat a lot of memory on huge file trees. This option cannot be used together with "\-\-cancel\-syscalls=mon_stat" To disable file/dir modification rechecking use empty value — "". The default value is "". .RE .PP .B \-k, \-\-timeout\-sync .I sync\-timeout .RS Sets timeout for syncing processes. .B clsync will die if syncing process alive more than .I sync\-timeout seconds. Set "0" to disable the timeout. The default value is "86400" ["24 hours"]. .RE .PP .B \-w, \-\-delay\-sync .I additional\-delay .RS Sets the minimal delay (in seconds) between syncs. The default value is "30". .RE .PP .B \-t, \-\-delay\-collect .I ordinary\-delay .RS Sets the delay (in seconds) to collect events about ordinary files and directories. The default value is "30". .RE .PP .B \-T, \-\-delay\-collect\-bigfile .I bigfiles\-delay .RS Sets the delay (in seconds) to collect events about "big files" (see .IR \-\-threshold\-bigfile ). The default value is "1800". .RE .PP .B \-B, \-\-threshold\-bigfile .I filesize\-threshold .RS Sets file size threshold (in bytes) that separates ordinary files from "big files". Events about "big files" are processed in another queue with a separate collecting delay. This is supposed to be used as a means of unloading IO resources. To disable detection of "big files" set "0" (zero). This can improve performance by removing necessity in extra lstat() syscall. The default value is "134217728" ["128 MiB"]. .RE .B \-\-cancel\-syscalls .I syscalls\-mask .RS Sets syscalls to be bypassed. This may be used for to squeeze more performance. Possible values: .RS .B mon_stat .RS Skip lstat() calls while handling files/dirs events. This makes unpossible to determine files sizes (that is used by .B \-\-threshold\-bigfile option) and to use option .BR \-\-modification\-signature . .RE .RE You can combine this values using commas. To disable this option just use empty value — "". The default value is "". .RE .PP .B \-L, \-\-lists\-dir .I tmpdir\-path .RS Sets directory path to output temporary events\-lists files. See .BR "SYNC HANDLER MODES" . Is not set by default. .RE .PP .B \-\-have\-recursive\-sync .RS Use action "recursivesync" instead of "synclist" for directories that were just marked (see .B "SYNC HANDLER MODES" case .BR shell ). Is not set by default. .RE .PP .B \-\-synclist\-simplify .RS Removes the first 3 parameters in list files of action "synclist" (see .B "SYNC HANDLER MODES" case .BR shell ). Is not set by default. .RE .\" .PP .\" .B \-A, \-\-auto\-add\-rules\-w .\" .RS .\" Forces clsync to create a "w-rule" for every non-"w-rule" (see .\" .BR RULES ). .\" .\" Not recommended to use in modes "rsyncdirect", "rsyncshell" and "rsyncso" .\" .\" Is not set by default. .\" .RE .PP .B \-\-rsync\-inclimit .I rsync\-includes\-line\-limit .RS Sets soft limit for lines count in files by path .IR rsync\-listpath . Unfortunately, rsync works very slowly with huge "\-\-include\-from" files. So, .B clsync splits that list with approximately .I rsync\-includes\-line\-limit lines per list if it's too big, and executes by one rsync instance per list part. Use value "0" to disable the limit. The default value is "20000". .RE .PP .B \-\-rsync\-prefer\-include .RS Forces .B clsync to prefer a "lot of includes" method instead of a "excludes+includes" for rsync on recursive syncing. See cases .BR rsyncshell , .B rsyncdirect and .B rsyncso of .BR "SYNC HANDLER MODES" . This option is not recommended. Is not set by default. .RE .PP .B \-x, \-\-ignore\-exitcode .I exitcode .RS Forces .B clsync to do not process exitcode .I exitcode of .I sync\-handler as an error. You can set multiple ignores by passing this option multiple times. Recommended values for rsync case is "24". You can set multiple values with listing a lot of "\-x" options (e.g. "\-x 23 \-x 24") or via commas (e.g. "\-x 23,24"). To drop the list use zero exitcode (e.g. "\-x 0"). For example you can use "\-x 0,23" to drop the list and set "23"-th exitcode to be ignored. Is not set by default (or equally is set to "0"). .RE .PP .B \-U, \-\-dont\-unlink\-lists .RS Do not delete list\-files after .I sync\-handler has finished. This may be used for debugging purposes. Is not set by default. .RE .PP .B \-\-fts\-experimental\-optimization .RS Enable experimental features to optimize file tree scanning while using .BR fts "(3)." The features will be enabled by default after appropriate testing. At the moment the option doesn't do anything but can be used in future. Is not set by default. .RE .PP .B \-F, \-\-full\-initialsync .RS Ignore filter rules from .I rules-file on initial sync. This may be useful for quick start or e.g. if it's required to sync "/var/log/" tree but not sync every change from there. Is not set by default. .RE .PP .B \-\-only\-initialsync .RS Exit after initial syncing on clsync start. Is not set by default. .RE .PP .B \-\-exit\-on\-no\-events .RS Exit if there's no events. Works like .IR \-\-only\-initialsync , but also syncs events collected while the initial syncing. Unlike .I \-\-only\-initialsync this option uses FS monitor subsystem to monitor for new events while the initial syncing. This may reduce performance. On the other hand this way may be used to be sure, that everything is synced at the moment before clsync will exit. Is not set by default. .RE .PP .B \-\-skip\-initialsync .RS Skip initial syncing on clsync start. Is not set by default. .RE .PP .B \-\-sync\-on\-quit .RS On SIGQUIT: clsync will perform one more final syncing to empty the queue of collected events before exit. Is not set by default. .RE .PP .B \-\-exit\-hook .I path\-of\-exit\-hook\-program .RS Sets path of program to be executed on clsync exit. If this parameter is set then clsync will exec on exit: .RS .I path\-of\-exit\-hook\-program label .RE The execution will be skipped if initial sync wasn't complete. Is not set by default. .RE .PP .B \-\-pre\-exit\-hook .I path\-of\-pre\-exit\-hook\-program .RS Sets path of program to be executed before the last sync iteration (see .IR "\-\-max\-iterations" ", " "\-\-exit\-on\-no\-events" " and " .BR SIGNALS ")." If this parameter is set then clsync will exec on exit: .RS .I path\-of\-pre\-exit\-hook\-program label .RE The execution will be skipped if initial sync wasn't complete. If .B clsync finishes due to .I \-\-exit\-on\-no\-events and .I \-\-pre\-exit\-hook is set then the pre\-exit hook will be executed and additional sync iteration will be triggered. Is not set by default. .RE .PP .B \-v, \-\-verbose .RS This option is supposed to increase verbosity. But at the moment there's no "verbose output" in the code, so the option does nothing. :) Is not set by default. .RE .PP .B \-d, \-\-debug .RS Increases debugging output. This may be supplied multiple times for more debugging information, up to a maximum of five "d" flags (more will do nothing), for example "\-d \-d \-d \-d \-d" or "\-d5" (equivalent cases) Is not set by default. .RE .PP .B \-\-dump\-dir .RS Directory to write clsync's instance information by signal 29 (see .BR SIGNALS ")." The directory shouldn't exists before dumping. Is set to "/tmp/clsync\-dump\-%label%" by default. .RE .PP .B \-q, \-\-quiet .RS Suppresses error messages. Is not set by default. .RE .PP .B \-\-monitor .I monitor\-subsystem .RS Switches FS monitor subsystem. Possible values: .RS .IR inotify .RS .BR inotify "(7) [Linux, (FreeBSD via libinotify)]" Native, fast, reliable and well tested Linux FS monitor subsystem. There's no essential performance profit to use "inotify" instead of "kevent" on FreeBSD using "libinotify". It backends to "kevent" anyway. FreeBSD users: The libinotify on FreeBSD is still not ready and unusable for .B clsync to sync a lot of files and directories. .RE .IR gio .RS Use .B gio library. Crossplatform and tested library that backends to kqueue on FreeBSD and inotify on Linux. See .B inotify and .B kqueue sections here for details. .B Not well tested. Use with caution! .RE .IR kqueue .RS .BR kqueue "(2) [FreeBSD, (Linux via libkqueue)]" A *BSD kernel event notification mechanism (inc. timer, sockets, files etc). This monitor subsystem cannot determine file creation event, but it can determine a directory where something happened. So .B clsync is have to rescan whole dir every time on any content change. Moreover, kqueue requires an open() on every watched file/dir. But FreeBSD doesn't allow one to open() symlink itself (without following) and it's highly invasively to open() pipes and devices. So .B clsync just won't call open() on everything except regular files and directories. Consequently, .B clsync cannot determine if something changed in symlink/pipe/socket and so on. However it still can determine if it will be created or deleted by watching the parent directory and rescaning it on every appropriate event. Also this API requires to open every monitored file and directory. So it may produce a huge amount of file descriptors. Be sure that .I kern.maxfiles is big enough (in FreeBSD). CPU/HDD expensive way. .B Not well tested. Use with caution! Linux users: The libkqueue on Linux is not working. He-he :) .RE .IR bsm .RS .BR bsm "(3) [FreeBSD]" Basic Security Module (BSM) Audit API. This is not a FS monitor subsystem, actually. It's just an API to access to audit information (inc. logs). .B clsync can setup audit to watch FS events and report it into log. After that .B clsync will just parse the log via .BR auditpipe "(4) [FreeBSD]." Reliable, but hacky way. It requires global audit reconfiguration that may hopple audit analysis. .B Warning! FreeBSD has a limit for queued events. In default FreeBSD kernel it's only 1024 events. So choose .B one of: .RS \- To patch the kernel to increase the limit. .br \- Don't use .B clsync on systems with too many file events. .br \- Use .I bsm_prefetch mode (but there's no guarantee in this case anyway). .RE See also option .IR \-\-exit\-on\-sync\-skip . .B Not well tested. Use with caution! Also file /etc/security/audit_control will be overwritten with: .RS #clsync .br .br dir:/var/audit .br flags:fc,fd,fw,fm,cl .br minfree:0 .br naflags:fc,fd,fw,fm,cl .br policy:cnt .br filesz:1M .RE unless it's already starts with "#clsync\\n" ("\\n" is a new line character). .RE .I bsm_prefetch .RS The same as .I bsm but all BSM events will be prefetched by an additional thread to prevent BSM queue overflow. This may utilize a lot of memory on systems with a high FS events frequency. However the thread may be not fast enough to unload the kernel BSM queue. So it may overflow anyway. .RE .RE The default value on Linux is "inotify". The default value on FreeBSD is "kqueue". .RE .PP .B \-l, \-\-label .I label .RS Sets a label for this instance of clsync. The .I label will be passed to .I sync\-handler every execution. The default value is "nolabel". .RE .PP .B \-h, \-\-help .RS Outputs options list and exits with exitcode "0". Is not set by default. .RE .PP .B \-V, \-\-version .RS Outputs clsync version and exits with exitcode "0". Is not set by default. .RE .PP .B \-\-cgroup\-group\-name .I cg\-group\-name .RS Set cgroup group name [see .BR cgroup_new_cgroup ()]. Is set to "clsync/%PID%" by default. .RE .SH SECURITY OPTIONS .B \-\-secure\-splitting .RS Implies "\-\-splitting=process \-\-check\-execvp\-arguments \-\-seccomp\-filter \-\-forbid\-devices" .RE .B \-u, \-\-uid .I uid .RS Drop user privileges to uid .I uid with .BR setuid (2) If there's a .BR capabilities (7) support then the default value is "nobody" (or "65534" if "nobody" not found), otherwise the option is not set by default; .PP .RE .B \-g, \-\-gid .I gid .RS Drop group privileges to gid .I gid with .BR setgid (2) If there's a .BR capabilities (7) support then the default value is "nogroup" (or "65534" if "nogroup" not found), otherwise the option is not set by default; .PP .RE .B \-\-privileged\-uid .I sync\-handler\-uid .RS An user ID to be used for the privileged process .BR "" "(see " "--splitting=process" ")". The default value is "$UID". .PP .RE .B \-\-privileged\-gid .I sync\-handler\-gid .RS A group ID to be used for the privileged process .BR "" "(see " "--splitting=process" ")". The default value is "$GID". .PP .RE .B \-\-sync\-handler\-uid .I sync\-handler\-uid .RS An user ID to be used for .IR sync\-handler . See .BR \-\-preserve\-capabilities . The default value is same as for .BR \-\-privileged-uid . .PP .RE .B \-\-sync\-handler\-gid .I sync\-handler\-gid .RS A group ID to be used for .IR sync\-handler . See .BR \-\-preserve\-capabilities . The default value is same as for .BR \-\-privileged-gid . .PP .RE .B \-C, \-\-preserve\-capabilities .I capabilities\-list .RS .B [Linux only, requires capabilities] Use .BR capset (2) and .BR prctl (2) to preserve "CAP_DAC_READ_SEARCH", "CAP_SETUID" or/and "CAP_SETGID" [see .BR capabilities (7)] Linux capability for process using .BR fts "(3), " inotify "(7) and " execve "(2)." This allows the preservation of enough FS privileges to watch a file tree and execute the .I sync\-handler with required uid and gid [see .B \-\-sync\-handler\-uid and .BR \-\-sync\-handler\-gid ] after dropping privileges via .BR setuid "(2) and " setgid "(2)" [see .B \-\-uid and .BR \-\-gid ] Possible values: .RS .B CAP_DAC_READ_SEARCH .RS To bypass FS read checks (for .BR fts " and " inotify ). .RE .B CAP_SETUID .RS To be able to use .BR setuid (2) before .BR execve (2) on the .BR sync\-handler . .RE .B CAP_SETGID .RS To be able to use .BR setgid (2) before .BR execve (2) on the .BR sync\-handler . .RE .B CAP_KILL .RS To be able to kill setuid()-ed processes .RE .br .br Any combinations of this values are also supported. The list may be presented as a comma separated values, like: .RS CAP_DAC_READ_SEARCH,CAP_SETUID,CAP_SETGID .RE .RE The default value is "CAP_DAC_READ_SEARCH,CAP_SETUID,CAP_SETGID,CAP_KILL" if the .B clsync runner have such privileges. .PP .RE .B \-\-inherit\-capabilities .RS .B [Linux only, requires capabilities] Sets a mode for capabilities inheriting. Possible values: .RS .B permitted .RS Inherits all permitted capabilities .RE .B dont-touch .RS Don't change inheritable capabilities set .RE .B clsync .RS Use .BR clsync 's effective capabilities set .RE .B empty .RS Reset all capabilities .RE .RE The default value is "empty". .RE .B \-\-splitting .I splitting\-type .RS Split the process/thread to privileged and non-privileged. This's an additional way to secure your system from any bug in .B clsync while running it with capabilities or root privileges. But .B clsync may utilize in few times more CPU resources. So it's a performance vs security trade off. You can essentialy reduce the overhead with using "high load locks" ("\-\-enable\-highload\-locks" of "./configure" file). If you're using this option and running the .I sync\-handler with the root user then it's highly recommended to enable .BR \-\-check\-execvp\-arguments , too. Otherwise in case of .B clsync security bug a hacker will be able to use execvp() with any arguments with root privileges. Possible values: .RS .B off .RS Disable this feature .RE .B thread .RS .B [Linux only, requires capabilities] Creates a separate thread for privileged operations. It's highly recommended to enable .B \-\-seccomp\-filter in this case. But that will forbid .BR \-\-threading . .RE .B process .RS More secure and portable way, but uses separate process and: .RS - forbids fanotify (that is not implemented yet anyway); .br - more complex code (and higher probability of error). .br - slower due to copying data between private and shared memory pages. .RE .B Recommended. .RE .RE Is set to "off" by default. .RE .B \-\-check\-execvp\-arguments .RS .B [Requires \-\-splitting=[thread|process]] .br .B [Blocks \-\-mode=direct] Enables execvp() arguments recheck in the privileged process (in case of their substitution to any exploit-given arguments). This option doesn't utilize a lot of CPU resources but forbids run-time changing of .I sync\-handler\-arguments and hook file paths. This option cannot be used in conjunction with .BR \-\-mode "=direct" due to an arbitrary number of arguments in this mode. Is not set by default. .RE .B \-\-add\-permitted\-hook\-files .I [hook\-path0,[hook\-path1[,...]]] .RS .B [Requires \-\-check\-execvp\-arguments] Adds paths to the list of permitted hook paths to bypass .B \-\-check\-execvp\-arguments checks. It may be required if you're going to change the hooks in run-time using .B \-\-custom\-signals or .BR \-\-socket . Is not set by default. .RE .B \-\-seccomp\-filter .RS .B [Linux only] Use .B seccomp filter to forbid syscalls that shouldn't be used by clsync. Forbid all syscalls for non-privileged process/thread, but .RS futex inotify_init1 alert stat fstat lstat open write close wait4 unlink tgkill clock_gettime rt_sigreturn brk mmap munmap wait4 rmdir exit_group select read rt_sigprocmask rt_sigaction nanosleep .RE Is not set by default. .RE .B \-\-permit\-mprotect .RS .B "[Requires \-\-seccomp\-filter]" Permits .BR mprotect (2) syscall. This syscall is required by .BR pthread_create (3), so it's required for .BR \-\-threading . Makes \-\-shm\-mprotect to be useless. Also it enables ability to change memory of privileged thread from non-privileged, so using of .B \-\-splitting=thread with this option is useless, too. Is set to "0" by default if \-\-splitting is set. Otherwise "1". .RE .B \-\-shm\-mprotect .RS .B "[Requires \-\-splitting=process]" Forbid writing or reading to/from shared memory when it shouldn't be. .BR mprotect (2) is used for the protection. This option is useless while .B \-\-permit\-mprotect is enabled. .RE .B \-\-chroot .I chroot\-directory .RS clsync chroot()\-s [see .BR chroot (2)] to directory .I chroot\-directory before any syncing processes. This option may be used in conjunction with .BR \-\-uid ", " \-\-gid or/and .B \-\-pivot\-root for security reasons. Remember! If you're chroot()\-ing somewhere, the .I sync\-handler will be limited by the chroot\-environment, too. If you're using rsync then you may want to "mount \-\-bind" some directories to the .IR chroot\-directory . Is not set by default. .PP .RE .B \-\-pivot\-root .I pivot\-root\-way .RS .B [Linux only, requires \-\-chroot] Sets a way of using .BR pivot_root (2) syscall to the .I chroot\-directory (to .BR umount (2) old rootfs). Possible values: .RS .B auto .RS Creates a directory "/dev/shm/clsync\-rootfs", .BR unshare "(2)-ing the mount namespace, " mount (2)-s the .I chroot\-directory to the directory and then .BR pivot_root "(2)-ing, " chroot "(2)-ing and " umount (2)-ing old rootfs. Directory "/dev/shm/clsync\-rootfs" won't be deleted after .B clsync finish. .RE .B auto-ro .RS The same as .B auto but mounts the directory with read-only option (MS_RDONLY). .RE .B direct .RS .BR unshare "(2)-ing the mount namespace, " pivot_root "(2)-ing, " chroot "(2)-ing and " umount (2)-ing old rootfs. Directory "old_root" should be created in .I chroot\-directory before running .B clsync in this mode. .RE .B off .RS Don't .BR pivot_root (2). .RE .RE The default value is "off". If .B \-\-chroot is used then recommended value is "auto\-ro". .RE .B \-\-mountpoints .I [mountpoint[,mountpoint[,mountpoint]]] .RS .B [Linux only] Umount (with MNT_DETACH) everything except listed mountpoints. Supposed to be used for security reasons as an alternative to .BR \-\-pivot\-root option. Is not set by default. .RE .B \-\-detach\-network .I detach\-network\-mode .RS .B [Linux only] Removes network in .B clsync instance. Possible values: .RS .B everywhere .RS Removes network for all processes. .RE .B non\-privileged .RS Removes network from non\-privileged process if option .B \-\-process\-splitting is enabled, otherwise doesn't do anything. .RE .B off .RS Don't do anything. .RE .RE The default value is "non\-privileged". .RE .B \-\-detach\-ipc .RS .B [Linux only] Make an own IPC namespace. Is set by default. .RE .B \-\-detach\-miscellanea .RS .B [Linux only] .BR unshare (2) on everything not listed above. Is not set by default. .RE .B \-\-forbid\-devices .RS .B [Linux only] Forbid any access to all devices except listed ones: .RS read access to: .RS /dev/console .br /dev/zero .br /dev/urandom .br /dev/random .RE write access to: .RS /dev/console .br /dev/null .RE .RE Is not set by default. .RE .SH PERFORMANCE Recommendations to improve the performance: .RS - Disable thread/process splitting. .br - Don't use clsync rules (use rules on sync-handler side) or/and use option "\-\-full\-initialsync" .br - Use option "\-B0". .br - Use option "\-\-cancel\-syscalls=mon_stat". .br - Use option "\-p safe" or "\-p full". .br - Disable debugging with "\-d0" or better disable debugging support at all with "./configure" option "\-\-enable\-debug=no" .br - Don't use option "\-\-exclude\-mount\-points" .br - Free memory for disk cache .br .RE You shouldn't follow all this recommendation blindfold. You should use only the ideas that fixes performance problems in your specific use case. And only if it's necessary. .SH SYNC HANDLER MODES .B clsync executes .I sync\-handler that supposed to take care of the actual syncing process. Therefore .B clsync is only a convenient way to run a syncing script. .B clsync can run .I sync\-handler in seven ways. Which way will be used depends on specified mode (see .IR \-\-mode ) .I sync\-handler\-arguments are used only in modes: .RS simple .br direct .br shell .br rsyncdirect .br rsyncshell .RE If .I sync\-handler\-arguments are not set then the default setting is used (see below). case .B simple .RS Executes for every syncing file/dir: .RS .I sync\-handler sync\-handler\-arguments .RE Default .I sync\-handler\-arguments are: .RS sync .I %label% %EVENT\-MASK% %INCLUDE\-LIST% .RE In this case, .I sync\-handler is supposed to non\-recursively sync file or directory by path .IR %INCLUDE\-LIST% . With .I %EVENT\-MASK% it's passed bitmask of events with the file or directory (see "/usr/include/linux/inotify.h"). Additional substitutions: .RS .B %EVENT\-MASK% .RS Is replaced by integer of events IDs. .RE .B %INCLUDE\-LIST% .RS Is replaced by absolute path of a file/dir to be synced. .RE .RE .RE case .B direct .RS Executes for every sync: .RS .I sync\-handler sync\-handler\-arguments .RE Default .I sync\-handler\-arguments are: .RS %INCLUDE\-LIST% %destination\-dir%/ .RE Additional substitutions: .RS .B %INCLUDE\-LIST% .RS Is replaced by a list of relative paths of files/dirs to be synced. .RE .RE .RE case .B shell .RS Executes for every sync (if .B recursivesync is not used instead): .RS .I sync\-handler sync\-handler\-arguments .RE Default .I sync\-handler\-arguments are: .RS synclist %label% %INCLUDE\-LIST\-PATH% .RE Default .I sync\-handler\-arguments for initial sync if .I \-\-have\-recursive\-sync is set are: .RS initialsync %label% %INCLUDE\-LIST% .RE In this case, .I sync\-handler is supposed to non\-recursively sync files and directories from list in a file by path %INCLUDE\-LIST\-PATH% on "synclist". Also .I sync\-handler is supposed to recursively sync data from directory by path %INCLUDE\-LIST\-PATH% with manual excluding extra files on "initialsync". Additional substitutions: .RS .B %TYPE% .RS Is replaced by "sync"/"initialsync". .RE .B %INCLUDE\-LIST\-PATH% .RS Is replaced by the path of the include list file. .RE .B %INCLUDE\-LIST% .RS Is replaced by a list of relative paths of files/dirs to be synced. .RE .RE Not recommended. Not well tested. .RE case .B rsyncdirect .RS Executes for every sync: .RS .I sync\-handler sync\-handler\-arguments .RE .I sync\-handler is supposed to be a path to .B rsync binary. Default .I sync\-handler\-arguments are: .RS \-aH \-\-delete \-\-exclude\-from %EXCLUDE\-LIST\-PATH% \-\-include\-from %INCLUDE\-LIST\-PATH% \-\-exclude='*' %watch\-dir%/ %destination\-dir%/ .RE if option .I \-\-rsync\-\-prefer\-include is not set and .RS \-aH \-\-delete \-\-include\-from %INCLUDE\-LIST\-PATH% \-\-exclude='*' %watch\-dir%/ %destination\-dir%/ .RE if the option is set Error code "24" from .I sync\-handler will be ignored in this case. We also recommend to ignore exitcode "23". Additional substitutions: .RS .B %INCLUDE\-LIST\-PATH% .RS Is replaced by the path of the include list file .RE .B %EXCLUDE\-LIST\-PATH% .RS Is replaced by the path of the exclude list file .RE .B %RSYNC\-ARGS% .RS Is replaced by default .IR sync\-handler\-arguments ", but" without "%watch\-dir%/ %destination\-dir%/" .RE .RE Recommended case. .RE case .B rsyncshell .RS Executes for every sync: .RS .I sync\-handler sync\-handler\-arguments .RE Default .I sync\-handler\-arguments are: .RS rsynclist %label% %INCLUDE\-LIST\-PATH% [%EXCLUDE\-LIST\-PATH%] .RE In this case, .I sync\-handler is supposed to run "rsync" application with parameters: \-aH \-\-delete\-before \-\-include\-from .I %INCLUDE\-LIST\-PATH% \-\-exclude '*' if option .I \-\-rsync\-prefer\-include is enabled. And with parameters: \-aH \-\-delete\-before \-\-exclude\-from .I %EXCLUDE\-LIST\-PATH% \-\-include\-from .I %INCLUDE\-LIST\-PATH% \-\-exclude '*' if option .I \-\-rsync\-prefer\-include is disabled. Additional substitutions: .RS .B %INCLUDE\-LIST\-PATH% .RS Is replaced by the path of the rsync include list file .RE .B %EXCLUDE\-LIST\-PATH% .RS Is replaced by the path of the rsync exclude list file .RE .RE Recommended case. .RE case .B rsyncso .RS In this case there's no direct exec*() calling. In this case .B clsync loads .I sync-handler as a shared library with .BR dlopen (3) and calls function "int clsyncapi_rsync(const char *inclist, const char *exclist)" from it for every sync. .br .B inclist is a path to file with rules for "\-\-include\-from" option of rsync. This argument is always not NULL. .br .B exclist is a path to file with rules for "\-\-exclude\-from" option of rsync. This argument is NULL if .B \-\-rsync\-prefer\-include is set. .br .I "Excludes takes precedence over includes." Also may be defined functions "int clsyncapi_init(ctx_t *, indexes_t *)" and "int clsyncapi_deinit()" to initialize and deinitialize the syncing process by this shared object. To fork the process should be used function "pid_t clsyncapi_fork(ctx_t *)" instead of "pid_t fork()" to make clsync be able to kill the child. See example file "clsync\-synchandler\-rsyncso.c". Recommended case. .RE case .B so .RS In this case there's no direct exec*() calling. In this case .B clsync loads .I sync-handler as a shared library with .BR dlopen (3) and calls function "int clsyncapi_sync(int n, api_eventinfo_t *ei)" from it for every sync. .B n is number of elements of .BR ei . .B ei is an array of structures with information about what and how to sync (see below). api_eventinfo_t is a structure: .RS struct api_eventinfo { .br uint32_t evmask; // event bitmask for file/dir by path .BR path . .br uint32_t flags; // flags of "how to sync" the file/dir .br size_t path_len; // strlen(path) .br const char *path; // the .B path to file/dir need to be synced .br eventobjtype_t objtype_old; // type of object by path .B path before the event. .br eventobjtype_t objtype_new; // type of object by path .B path after the event. .br }; .br typedef struct api_eventinfo api_eventinfo_t; .RE The event bitmask (evmask) values can be learned from "/usr/include/linux/inotify.h". There may be next flags' values (flags): .RS enum eventinfo_flags { .br EVIF_NONE = 0x00000000, // No modifier .br EVIF_RECURSIVELY = 0x00000001 // sync the file/dir recursively .br }; .RE .br Flag "EVIF_RECURSIVELY" may be used if option .I \-\-have\-recursive\-sync is set. Is that a file or directory by path .B path can be determined with .B objtype_old and .BR objtype_new . .br .B objtype_old reports about which type was the object by the path before the event. .br .B objtype_new reports about which type became the object by the path after the event. .B objtype_old and .BR objtype_new have type .BR eventobjtype_t . .RS enum eventobjtype { .br EOT_UNKNOWN = 0, // Unknown .br EOT_DOESNTEXIST = 1, // Doesn't exist (not created yet or already deleted) .br EOT_FILE = 2, // File .br EOT_DIR = 3, // Directory .br } typedef enum eventobjtype eventobjtype_t; .RE Also may be defined functions "int clsyncapi_init(options_t *, indexes_t *)" and "int clsyncapi_deinit()" to initialize and deinitialize the syncing process by this shared object. To fork the process should be used function "pid_t clsyncapi_fork(options_t *)" instead of "pid_t fork()" to make clsync be able to kill the child. See example file "clsync\-synchandler\-so.c". Recommended case. .RE .RE .SH ENVIRONMENT VARIABLES Recognized variables - variables used by clsync. .B "Recognized variables" .RS HOME - user's HOME directory, clsync looks for configuration file here .RE .RS TMPDIR - use this directory as a prefix to create clsync temporary directory inside, if unset .I /tmp will be used .RE Output variables - variables that are set by clsync before calling .IR sync-handler . .B "Output variables" .RS CLSYNC_STATUS - .BR clsync 's status (see possible statuses in description of .IR \-\-status\-file ) .RE .RS CLSYNC_ITERATION - count of done synchronizaton iterations after initial sync see \-\-max\-iterations option .RE .SH RULES Filter rules can be used to set which events clsync should monitor and which events it should ignore. .B Caution! This rules doesn't guarantee that filtered file/dir won't be synced. This can occur because file or directory can appear in the moment of .B sync\-handler running (or after it but before the .B sync\-handler will reach the directory), so it'll be too late to add an exclusion. If you need a guarantee of file syncing preventing you can use internal filter rules of the .B sync\-handler program (for example, rsync has options "\-\-exclude", "\-\-exclude\-from" and "\-\-filter") or use disable any "recursive" syncs in .B clsync (and remove "\-av" option of rsync if it's used). To disable recursive syncs you can use: .RS .B simple .RS Already non-recursive .RE .B direct .RS Already non-recursive .RE .B shell .RS Don't enable option \-\-have\-recursive\-sync. .RE .B rsyncdirect .RS Use option \-\-rsync\-prefer\-include and set .I sync\-handler\-arguments to \-lptgoD \-\-delete \-\-include\-from %INCLUDE\-LIST\-PATH% \-\-exclude='*' %watch\-dir%/ %destination\-dir%/ .RE .B rsyncshell .RS Use option \-\-rsync\-prefer\-include. .RE .B rsyncso .RS Use option \-\-rsync\-prefer\-include. .RE .B so .RS Don't enable option \-\-have\-recursive\-sync. .RE .RE Filter rules can be placed into .I rules\-file with one rule per line. Rule format: .I [+\-][fdWwms*]regexp .RS .I + \- means include; .br .I \- \- means exclude; .br .I f \- means file; .br .I d \- means directory (the same as an combination of "w" + "m" + "s"); .br .I w \- means walking to directory; .br .I m \- means monitor events in the directory; .br .I s \- means sync the the directory if modified; .br .I W \- means walk + monitor the directory (the same as an combination of "w" + "m"); .br .I * \- means all. .RE For example: \-*^/[Tt]est It's not recommended to use .I w rules in modes "rsyncdirect", "rsyncshell" and "rsyncso". .BR rsync (1) allows one to set syncing and walking only together in "\-\-include" rules ("\-\-files\-from" is not appropriate due to problem with syncing files deletions). So there may be problems with clsync's .I w rules in this cases. More examples: Syncing pwdb files and sshd_config (non-rsync case): .RS .br # which files to sync: .br +f^passwd$ .br +f^group$ .br +f^shadow$ .br +f^ssh/sshd_config$ .br .br # walk and monitor next directories: .br +W^$ .br +W^ssh$ .br .br # forbid the rest: .br \-* .RE .\" Syncing pwdb files and sshd_config (non-rsync case with option .\" .IR \-\-auto\-add\-rules\-w ): .\" .RS .\" +f^passwd$ .\" .br .\" +f^group$ .\" .br .\" +f^shadow$ .\" .br .\" +f^ssh/sshd_config$ .\" .br .\" \-* .\" .RE Syncing pwdb files and sshd_config (rsync case): .RS +f^passwd$ .br +f^group$ .br +f^shadow$ .br +f^ssh/sshd_config$ .br +d^$ .br +d^ssh$ .br \-* .RE Syncing /srv/lxc tree (rsync case): .RS \-d/sess(ion)?s?$ .br \-f/tmp/ .br +* .RE .SH SIGNALS 1 \- (HUP) rereads filter rules 2 \- (INT) exits without waiting of syncing processes ("hard kill", kills children) 3 \- (QUIT) waits for current syncing processes and exit ("soft kill", waits for children). See also .IR \-\-sync\-on\-quit . 10 \- runs threads' GC function 12 \- runs full resync 15 \- (TERM) exits without waiting of syncing processes ("hard kill", kills children) 16 \- interrupts sleep()/select() and wait() [for debugging and internal uses] 29 \- dump information to .IR dump\-dir [for debugging] If you need to kill clsync but leave children then you can use 9-th (KILL) signal. .SH DIAGNOSTICS .B clsync misses events: .RS Try to run command: sysctl fs.inotify.max_queued_events=1048576 .RE Initial rsync process works very slow on clsync start .RS Probably there's too huge exclude list is passed to rsync. This can happened if you're excluding with regex in clsync's rules a lot of thousands files. They will be passed to rsync's exclude list one by one. To diagnose it, you can use "\-U" option and look into .I rsync\-exclude\-listpath file (see .B "SYNC HANDLER" case .BR d ) To prevent this, it's recommended to write such rules for rsync directly (not via clsync). For example, often problem is with PHP's session files. You shouldn't exclude them in clsync's rules with "\-f/sess_.*", but you should exclude it in rsync directly (e.g with «\-\-exclude "sess_*"»). .RE The following diagnostics may be issued on stderr: Error: Cannot inotify_add_watch() on [...]: No space left on device (errno: 28) .RS Not enough inotify watching descriptors is allowed. It can be fixed by increasing value of "sysctl fs.inotify.max_user_watches" .RE Error: Got non-zero exitcode .I exitcode [...] .RS .I sync\-handler returned non-zero exitcode. Probably, you should process exitcodes in it or your syncer process didn't worked well. I case of using rsync, you can find the exitcodes meanings in .BR "man 1 rsync" . If .I exitcode equals to 23 and you're using .B clsync in conjunction with .BR rsync , this may happen, for example, in the following cases: .RS \- Not enough space on destination. \- You're running clsync with .B \-\-threading=full and rsync with .BR \-\-backup . .URL https://bugzilla.samba.org/show_bug.cgi?id=10081 "See a bugreport" . .RE To confirm the problem, you can try to add "return 0" or "exit 0" into your .IR sync\-handler . .RE .B "Bad system call" .RS If \-\-use\-seccomp option is enabled then the error is probably caused by using of forbidden syscall. It's a .B clsync bug or hack attack attempt. .RE To get support see .BR SUPPORT . .SH CONFIGURATION FILE .B clsync supports configuration file. By default .B clsync tries to read next files (in specified order): .RS ~/.clsync.conf .br /etc/clsync/clsync.conf .RE This may be overridden with option .IR \-\-config\-file . .B clsync reads only one configuration file. In other words, if option .I \-\-config\-file is not set and file .B ~/.clsync.conf is accessible and parsable, .B clsync will not try to open .BR /etc/clsync/clsync.conf . Command line options have precedence over config file options. Configuration file is parsed with glib's g_key_file_* API. That means, that config should consits from groups (blocks) of key-value lines as in the example: .RS [default] .br background = 1 .br mode = rsyncshell .br debug = 0 .br output = syslog .br label = default .br pid\-file = /var/run/clsync\-%label%.pid [debug] .br config\-block\-inherits = default .br debug = 5 .br background = 0 .br output = stderr [test] .br mode=rsyncdirect .br debug=3 .RE Also glib's .B gkf API doesn't support multiple assignments. If you need to list some values (e.g. exitcodes) just list them with commas in single assignment (e.g. "ignore\-exitcode=23,24"). In this example there're 3 blocks are set - "default", "debug" and "test". And block "debug" inherited setup of block "default" except options "debug", "background" and "output". By default .B clsync uses block with name "default". Block name can be set by option .IR \-\-config\-block . .SH CLUSTERING Not implemented yet. .B Don't try to use cluster functionality. Not described yet. .SH EXAMPLES .B Mirroring a directory: .RS clsync \-Mrsyncdirect \-W/path/to/source_dir \-D/path/to/destination_dir .RE .B Syncing 'authorized_keys' files: .RS mkdir \-p /etc/clsync/rules .br printf "+w^$\\n+w^[^/]+$\\n+W^[^/]+/.ssh$\\n+f^[^/]+/.ssh/authorized_keys$\\n-*" > /etc/clsync/rules/authorized_files_only .br clsync \-Mdirect \-Scp \-W/mnt/master/home/ \-D/home \-R/etc/clsync/rules/authorized_files_only \-\- \-Pfp \-\-parents %INCLUDE\-LIST% %destination\-dir% .RE .B Mirroring a directory, but faster: .RS clsync \-w5 \-t5 \-T5 \-Mrsyncdirect \-W/path/to/source_dir \-D/path/to/destination_dir .RE .B Instant mirroring of a directory: .RS clsync \-w0 \-t0 \-T0 \-Mrsyncdirect \-W/path/to/source_dir \-D/path/to/destination_dir .RE .B Making two directories synchronous: .RS clsync \-Mrsyncdirect \-\-background \-z /var/run/clsync0.pid \-\-output syslog \-Mrsyncdirect \-W/path/to/dir1 \-D/path/to/dir2 \-\-modification\-signature '*' .br clsync \-Mrsyncdirect \-\-background \-z /var/run/clsync1.pid \-\-output syslog \-Mrsyncdirect \-W/path/to/dir2 \-D/path/to/dir1 \-\-modification\-signature '*' .RE .B Fixing privileges of a web-site: .RS clsync \-w3 \-t3 \-T3 \-x1 \-W/var/www/site.example.org/root \-Mdirect \-Schown \-\-uid 0 \-\-gid 0 \-Ysyslog \-b1 \-\-modification\-signature uid,gid \-\- \-\-from=root www\-data:www\-data %INCLUDE\-LIST% .RE .B "'Atomic' sync:" .RS clsync \-\-exit\-on\-no\-events \-\-max\-iterations=20 \-\-mode=rsyncdirect \-W/var/www_new \-Srsync \-\- %RSYNC\-ARGS% /var/www_new/ /var/www/ .RE .B Moving a web-server: .RS clsync \-\-exit\-on\-no\-events \-\-max\-iterations=20 \-\-pre\-exit\-hook=/root/stop\-here.sh \-\-exit\-hook=/root/start\-there.sh \-\-mode=rsyncdirect \-\-ignore\-exitcode=23,24 \-\-retries=3 \-W /var/www \-S rsync \-\- %RSYNC\-ARGS% /var/www/ rsync://clsync@another-host/var/www/ .RE .B Copying files to slave-nodes using .BR pdcp (1): .RS clsync \-Msimple \-S pdcp \-W /opt/global \-b \-Y syslog \-\- \-a %INCLUDE\-LIST% %INCLUDE\-LIST% .RE .B Copying files to slave-nodes using .BR uftp (1): .RS clsync \-Mdirect \-S uftp \-W/opt/global \-\-background=1 \-\-output=syslog \-\- \-M 248.225.233.1 %INCLUDE\-LIST% .RE .B A dry running to see .BR rsync (1) .B arguments that clsync will use: .RS clsync \-Mrsyncdirect \-S echo \-W/path/to/source_dir \-D/path/to/destination_dir .RE .B An another dry running to look how clsync will call .BR pdcp (1): .RS clsync \-Msimple \-S echo \-W /opt/global \-b0 \-\- pdcp \-a %INCLUDE\-LIST% %INCLUDE\-LIST% .RE .B Automatically run 'make build' if any '*.c' file changed .RS printf "%s\\n" "+f\.c$" "\-f" | clsync \-\-have-recursive-sync \-W . \-R /dev/stdin \-Mdirect \-r1 \-\-ignore\-failures \-t1 \-w1 \-Smake \-\- build .RE More working examples you can try out in "/usr/share/doc/clsync/examples/" directory. Copy this directory somewhere (e.g. into "/tmp"). And try to run "clsync\-start\-rsync.sh" in there. Any files/directories modifications in "testdir/from" will be synced to "testdir/to" in a few seconds. .RE .SH AUTHOR Dmitry Yu Okunev 0x8E30679C .SH SUPPORT You can get support on official IRC-channel in Freenode "#clsync" or on github's issue tracking system of .URL https://github.com/clsync/clsync "the clsync repository" . Don't be afraid to ask about clsync configuration, ;). .SH "SEE ALSO" .BR rsync (1), .BR pthreads (7), .BR inotify (7) .BR kqueue (2)