cyrus-sync_client8
Cyrus imap documentation client side of the synchronization (replication) engine
Overview
sync_client is the client side of the replication system. It runs on the client (master) system and connects to the target (replica) system and generates an appropriate sequence of transactions to synchronize the replica system with the master system.
sync_client reads its configuration options out of the imapd.conf(5) file unless specified otherwise by -C.
Options
-
-C config-file -
Use the specified configuration file config-file rather than the default imapd.conf(5).
-
-A, --all-users -
All users mode. Sync every user on the server to the replica (doesn't do non-user mailboxes at all... this could be considered a bug and maybe it should do those mailboxes independently)
-
-d delay, --delay=delay -
Minimum delay between replication runs in rolling replication mode. Larger values provide better efficiency as transactions can be merged. Smaller values mean that the replica system is more up to date and that you don't end up with large blocks of replication transactions as a single group. Default: 3 seconds.
-
-f input-file, --input-file=input-file -
In mailbox or user replication mode: provides list of users or mailboxes to replicate. In rolling replication mode, specifies an alternate log file (
sync_clientwill exit after processing the log file).
-
-F shutdown-file, --shutdown-file=shutdown-file -
Rolling replication checks for this file at the end of each replication cycle and shuts down if it is present. Used to request a nice clean shutdown at the first convenient point. The file is removed on shutdown. Overrides
sync_shutdown_fileoption in imapd.conf(5).
-
-l, --verbose-logging -
Verbose logging mode.
-
-L, --local-only -
Perform only local mailbox operations (do not do mupdate operations). This feature was introduced in version 3.0.
-
-m, --mailboxes -
Mailbox mode. Remaining arguments are list of mailboxes which should be replicated.
-
-n channel, --channel=channel -
Use the named channel for rolling replication mode. If multiple channels are specified in
sync_log_channelsthen use one of them. This option is probably best combined with-Sto connect to a different server with each channel.
-
-N, --skip-locked -
Use non-blocking sync_lock (combination of IP address and username) to skip over any users who are currently syncing.
-
-o, --connect-once -
Only attempt to connect to the backend server once.
Without this option,
sync_clientwill retry failed connections indefinitely, waiting up tosync_reconnect_maxwait(default: 20m) between attempts.
-
-O, --no-copyback -
No copyback mode. Replication will stop if the replica reports a CRC error, rather than doing a full mailbox sync. Useful if moving users to a new server, where you don't want any errors to cause the source servers to change the account.
-
-p partition, --dest-partition=partition -
In mailbox or user replication mode: provides the name of the partition on the replica to which the mailboxes/users should be replicated.
-
-r, --rolling -
Rolling (repeat) replication mode. Pick up a list of actions recorded by the lmtpd(8), imapd(8), pop3d(8) and nntpd(8) daemons from the file specified in
sync_log_file. Repeat untilsync_shutdown_fileappears. Alternative log and shutdown files can be specified with-fand-F.In this invocation, sync_client will background itself to run as a daemon.
-
-R, --foreground-rolling -
As for
-r, but without backgrounding.
-
-1, --rolling-once -
As for
-R, but only process a single log file before exiting.
-
-s, --sieve-mode -
Sieve mode. Remaining arguments are list of users whose Sieve files should be replicated. Principally used for debugging purposes: not exposed to sync_client(8).
-
-S servername, --server=servername -
Tells
sync_clientwith which server to communicate. Overrides thesync_hostconfiguration option.
-
-t timeout, --timeout=timeout -
Timeout for single replication run in rolling replication.
sync_clientwill negotiate a restart after this many seconds. Default: 600 seconds
-
-u, --userids -
User mode. Remaining arguments are list of users who should be replicated.
-
-v, --verbose -
Verbose mode. Use twice (-v -v) to log all protocol traffic to stderr.
-
-w interval, --delayed-startup=interval -
Wait this long before starting. This option is typically used so that we can attach a debugger to one end of the replication system or the other.
-
-z, --require-compression -
Require compression. The replication protocol will always try to enable deflate compression if both ends support it. Set this flag when you want to abort if compression is not available.
-
-a, --stage-to-archive -
Request the stage-to-archive feature. If the remote end has the
archive_enabledoption set, then it will stage incoming replication on the archive partition instead of the spool partition. If the remote end does not support it, replication will proceed as though-awas not provided. This option is useful when standing up a new replica of an existing server, as most of the stored mail is likely older than the archive threshold and so is destined for the archive partition anyway. By staging on that partition, Cyrus can avoid a cross-partition copy for every message.
Examples
On a replication master, the following would be added to the START section of cyrus.conf(5):
syncclient cmd="/usr/lib/cyrus/bin/sync_client -r"
[NB: More examples needed]
Files
/etc/imapd.conf
History
- Debian 13 (Trixie): the text shown here
- Debian 12 (Bookworm)
- Debian 10 (Buster)
- Debian 9 (Stretch)
- Debian 8 (Jessie) to Debian 7 (Wheezy)
--all-users since Debian 13 (Trixie);
--channel since Debian 13 (Trixie);
--connect-once since Debian 13 (Trixie);
--delay since Debian 13 (Trixie);
--delayed-startup since Debian 13 (Trixie);
--dest-partition since Debian 13 (Trixie);
--foreground-rolling since Debian 13 (Trixie);
--input-file since Debian 13 (Trixie);
--local-only since Debian 13 (Trixie);
--mailboxes since Debian 13 (Trixie);
--no-copyback since Debian 13 (Trixie);
--require-compression since Debian 13 (Trixie);
--rolling since Debian 13 (Trixie);
--rolling-once since Debian 13 (Trixie);
--server since Debian 13 (Trixie);
--shutdown-file since Debian 13 (Trixie);
--sieve-mode since Debian 13 (Trixie);
--skip-locked since Debian 13 (Trixie);
--stage-to-archive since Debian 13 (Trixie);
--timeout since Debian 13 (Trixie);
--userids since Debian 13 (Trixie);
--verbose since Debian 13 (Trixie);
--verbose-logging since Debian 13 (Trixie);
-1 since Debian 12 (Bookworm);
-A since Debian 9 (Stretch);
-C since Debian 10 (Buster);
-F since Debian 10 (Buster);
-L since Debian 10 (Buster);
-N since Debian 12 (Bookworm);
-O since Debian 10 (Buster);
-R since Debian 13 (Trixie);
-S since Debian 10 (Buster);
-a since Debian 13 (Trixie);
-d since Debian 10 (Buster);
-f since Debian 10 (Buster);
-p since Debian 10 (Buster);
-t since Debian 10 (Buster);
-w since Debian 10 (Buster).