Notes for Packagers¶
Sample configuration files¶
There are several samples of cyrus.conf(5) and
imapd.conf(5) located in the
doc/examples directory of
the distribution tarball. Please install these to your preferred
documentation directory (i.e.
/usr/share/doc/cyrus-imapd) as a
reference for your users.
The configuration file for master: cyrus.conf¶
When installing a predefined cyrus.conf(5) for your users, please pay attention to new features and how these may impact users. For example, for some time now, Cyrus has supported placing several standard DB files in temporary, or ephemeral, storage, such as memory backed filesystems like tmpfs (see below). This both boosts efficiency and ensures DB consistency in event of a crash or other system disruptive events. But, in light of this, actions which depend on the existence of these database files should not be placed in the START section of cyrus.conf(5).
A new section, DAEMON, was added to cyrus.conf(5) in version 2.5. Please consult cyrus.conf(5) for details. Please refer to the notes in Section Descriptions pertaining to the distinctions between START, EVENTS and DAEMON sections.
In brief, the sorts of things which should go into the different sections are:
- Periodic processes which will be started by master(8) as specified.
- Programs which should be spawned by master(8) which it should shut down and clean up after.
The configuration file for the various programs: imapd.conf¶
The sample imapd.conf(5) files must be adapted for use from site to site. Here, therefore, we’ll attempt to point you towards some reasonable settings which take advantage of recent improvements and features, and may help guide you and your users to a better performing Cyrus installation.
Ephemeral files and temporary filesystems¶
In addition to Unix domain sockets and lock files, several databases
used by Cyrus programs may be located in temporary filesystems, such as
those backed by RAM (i.e. tmpfs, md, etc.). Here’s a list of such
files. In this example, the filesystem
/run is on tmpfs:
proc_path: /run/cyrus/proc mboxname_lockpath: /run/cyrus/lock duplicate_db_path: /run/cyrus/deliver.db statuscache_db_path: /run/cyrus/statuscache.db ptscache_db_path: /run/cyrus/ptscache.db tls_sessions_db_path: /run/cyrus/tls_sessions.db lmtpsocket: /run/cyrus/socket/lmtp idlesocket: /run/cyrus/socket/idle notifysocket: /run/cyrus/socket/notify
Any process which depends on these files already existing should not be placed in the START section of cyrus.conf(5), or the server will not start as expected.
New default settings¶
With the introduction of version 3.0, the defaults for some settings have changed. Please consult Upgrading to 3.0 for details.
There are several features either new to version 3.0, or newly improved. Some of these may be features which previously were not considered ripe for packaging, but merit new consideration.
Please see the release notes Major changes since the 2.5.x series for more details and other recent changes.
- Server-side threading with reduced protocol chatter for mobile or other high-latency clients.
- Required for JMAP support.
- See the
conversationsoptions in imapd.conf(5)
- JSON Mail Access Protocol
- Follow-on successor to IMAP (“J comes after I”) with a special focus on mobile and other clients with high-latency or unreliable connectivity.
- Includes Calendaring, Contacts, Conversations, message delivery.
- Higher quality full-text search support.
- Required for JMAP support.
- See the
search_engineoption in imapd.conf(5) and
doc/README.xapianin the source distribution.
- Archive partitions
- Automatically migrate messages from posh, fast storage (think SSD) to cheap, slow storage (spinning rust).
- Requires addition of an archive partition for each data partition.
archive_*options in imapd.conf(5)
- Replication-based backup to dedicated instance with efficient, compact scheme.
- See Cyrus Backups
Please consider enabling these features in the imapd.conf(5) you ship in your packages.
Listing named services through
/etc/services aids in cross-system consistency and cross-platform interoperability. Furthermore, it enables administrators and users to refer to the service by name (for example in
/etc/cyrus.conf, ‘listen=mupdate’ can be specified instead of ‘listen=3905’).
Some of the services Cyrus IMAP would like to see available through
/etc/services have not been assigned an IANA port number, and few have configuration options.
The Cyrus IMAP server provides service interfaces via either TCP/IP
ports or Unix domain sockets. For the former, Cyrus requires that there
are proper entries in the host’s
/etc/services file. The following
are required for any host using the listed services:
pop3 110/tcp # Post Office Protocol v3 nntp 119/tcp # Network News Transport Protocol imap 143/tcp # Internet Mail Access Protocol rev4 imsp 406/tcp # Internet Message Support Protocol (deprecated) nntps 563/tcp # NNTP over TLS imaps 993/tcp # IMAP over TLS pop3s 995/tcp # POP3 over TLS kpop 1109/tcp # Kerberized Post Office Protocol lmtp 2003/tcp # Lightweight Mail Transport Protocol service smmap 2004/tcp # Cyrus smmapd (quota check) service csync 2005/tcp # Cyrus replication service mupdate 3905/tcp # Cyrus mupdate service sieve 4190/tcp # timsieved Sieve Mail Filtering Language service
Make sure that these lines are present or add them if they are missing.