1SYNC_CLIENT(8) Cyrus IMAP SYNC_CLIENT(8)
2
6 sync_client - Cyrus IMAP documentation
7 Client side of the synchronization (replication) engine
9
11 sync_client [ -v ] [ -l ] [ -L ] [ -z ] [ -C config-file ] [ -S server-name ]
12 [ -f input-file ] [ -F shutdown_file ] [ -w wait_interval ]
13 [ -t timeout ] [ -d delay ] [ -r ] [ -n channel ] [ -u ] [ -m ]
14 [ -p partition ] [ -A ] [ -N ] [ -s ] [ -O ] objects...
15
17 sync_client is the client side of the replication system. It runs on
18 the client (master) system and connects to the target (replica) system
19 and generates an appropriate sequence of transactions to synchronize
20 the replica system with the master system.
21 sync_client reads its configuration options out of the imapd.conf(5)
23 file unless specified otherwise by -C.
24
26 -C config-file
27 Use the specified configuration file config-file rather than the
28 default imapd.conf(5).
29 -A All users mode. Sync every user on the server to the replica
31 (doesn’t do non-user mailboxes at all… this could be considered
32 a bug and maybe it should do those mailboxes independently)
33 -d delay
35 Minimum delay between replication runs in rolling replication
36 mode. Larger values provide better efficiency as transactions
37 can be merged. Smaller values mean that the replica system is
38 more up to date and that you don’t end up with large blocks of
39 replication transactions as a single group. Default: 3 seconds.
40 -f input-file
42 In mailbox or user replication mode: provides list of users or
43 mailboxes to replicate. In rolling replication mode, specifies
44 an alternate log file (sync_client will exit after processing
45 the log file).
46 -F shutdown-file
48 Rolling replication checks for this file at the end of each
49 replication cycle and shuts down if it is present. Used to re‐
50 quest a nice clean shutdown at the first convenient point. The
51 file is removed on shutdown. Overrides sync_shutdown_file option
52 in imapd.conf(5).
53 -l Verbose logging mode.
55 -L Perform only local mailbox operations (do not do mupdate opera‐
57 tions). This feature was introduced in version 3.0.
58 -m Mailbox mode. Remaining arguments are list of mailboxes which
60 should be replicated.
61 -n channel
63 Use the named channel for rolling replication mode. If multiple
64 channels are specified in sync_log_channels then use one of
65 them. This option is probably best combined with -S to connect
66 to a different server with each channel.
67 -N Use non-blocking sync_lock (combination of IP address and user‐
69 name) to skip over any users who are currently syncing.
70 -o Only attempt to connect to the backend server once rather than
72 waiting up to 1000 seconds before giving up.
73 -O No copyback mode. Replication will stop if the replica reports a
75 CRC error, rather than doing a full mailbox sync. Useful if mov‐
76 ing users to a new server, where you don’t want any errors to
77 cause the source servers to change the account.
78 -p partition
80 In mailbox or user replication mode: provides the name of the
81 partition on the replica to which the mailboxes/users should be
82 replicated.
83 -r Rolling (repeat) replication mode. Pick up a list of actions
85 recorded by the lmtpd(8), imapd(8), pop3d(8) and nntpd(8) dae‐
86 mons from the file specified in sync_log_file. Repeat until
87 sync_shutdown_file appears.
88 -1 Like rolling replication, but only process a single file before
90 exiting.
91 -s Sieve mode. Remaining arguments are list of users whose Sieve
93 files should be replicated. Principally used for debugging pur‐
94 poses: not exposed to sync_client(8).
95 -S servername
97 Tells sync_client with which server to communicate. Overrides
98 the sync_host configuration option.
99 -t timeout
101 Timeout for single replication run in rolling replication.
102 sync_client will negotiate a restart after this many seconds.
103 Default: 600 seconds
104 -u User mode. Remaining arguments are list of users who should be
106 replicated.
107 -v Verbose mode. Use twice (-v -v) to log all protocol traffic to
109 stderr.
110 -w interval
112 Wait this long before starting. This option is typically used so
113 that we can attach a debugger to one end of the replication sys‐
114 tem or the other.
115 -z Require compression. The replication protocol will always try
117 to enable deflate compression if both ends support it. Set this
118 flag when you want to abort if compression is not available.
119
121 On a replication master, the following would be added to the START sec‐
122 tion of cyrus.conf(5):
123 syncclient cmd="/usr/lib/cyrus/bin/sync_client -r"
125 [NB: More examples needed]
127
129 The -L feature, local updates only, was added in version 3.0.
130
132 /etc/imapd.conf
133
135 sync_server(8), cyrus.conf(5), imapd.conf(5), master(8)
136
138 The Cyrus Team, David Carter (dpc22@cam.ac.uk), Ken Murchison
139 (ken@oceana.com), Nic Bernstein (Onlight)
140
142 1993–2022, The Cyrus Team
1433.6.0 December 12, 2022 SYNC_CLIENT(8)