Configuration file locations
The main configuration file for Cyrus IMAP is imapd.conf(5)
and its path is compiled into the executable files, based upon the
--sysconfdir build flag. For many utilities, this may be
overridden at runtime via the -C flag, followed by the name of the
configuration file to use. For example:
ctl_mboxlist -C /usr/local/etc/imapd.conf -d -f mailboxes.dump
The main configuration directory is referred to as <configdirectory>
in Cyrus IMAP documentation, and is set via the configdirectory
entry in imapd.conf(5).
While Cyrus itself has no default values for this setting, most
distributions use /var/lib/imap or /var/lib/cyrus.
State Databases
Despite the name, most of what's stored in <configdirectory> is state
information. Here's a list of files typically located therein:
The links above document the purpose, DB type and choices for those files. You may adjust the locations of these database files via various settings in imapd.conf(5):
Ephemeral Databases
Several of the state databases may be located in RAM-backed locations,
such as /run or /var/run or where ever your OS roots such
filesystems (i.e. tmpfs on Linux or mfs on FreeBSD). Cyrus 3.0 will
recreate the following databases for you automatically:
duplicate delivery (deliver.db),
TLS cache (tls_sessions.db),
PTS cache (ptscache.db),
STATUS cache (statuscache.db).
Relocating these DBs to ephemeral storage will place less IO load on your disks and tend to run faster.
Note
Please be warned that some packagers place tasks such as
tlsprune (tls_prune(8)) in the START{} stanza
of cyrus.conf(5). This will cause a startup problem if
the tls_sessions_db is not present. The solution to this is to
remove the tlsprune task from START{} and schedule it in
EVENTS{}, further down.
State Directories
In addition to the files, are several directories:
lock (per-mailbox lock files)
log (per-user telemetry log directories)
proc (per-process state data)
ptclient (PT Loader Unix-domain socket)
quota (per-quotaroot quota state data)
sieve (per-user sieve message filter scripts)
socket (per-service Unix-domain sockets)
sync (per-replica directories with sync log files)
user (per-user DBs, see next section)
As with the DB files, above, many of these, too, may be relocated via settings in imapd.conf(5):
Note
If your configuration uses quota_db: quotalegacy,
then quota_db_path points to the base of the quota directory
hierarchy. If you use any other DB type, then this will be
the actual filename.
Per-user State Directories
There are several things tracked per-user, and the data files for these items, such as subscriptions and seen state, are stored in <configdirectory>/user. These files may not be relocated from <configdirectory>. They are:
Please follow those links for more information on these files.