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cyrus2dovecot - convert Cyrus folders to Dovecot


cyrus2dovecot [-cdmq] [-C cyrus-inbox] [-D dovecot-inbox] [-E edit-foldernames] [-F dovecot-uidlist-format] [-H dovecot-host] [-N default-quota] [-O cyrus-quota-format] [-Q cyrus-quota] [-S cyrus-seen] [-U cyrus-sub] [user ...]

cyrus2dovecot -h | -v


cyrus2dovecot converts the e-mails of one or more users from Cyrus format to Dovecot Maildir++ folders. If no user is specified, the user names are read from the standard input, one per line. Message UIDs, INTERNALDATEs, IMAP folder subscriptions, the UIDVALIDITY and UIDNEXT values for each folder, as well as all IMAP flags (including the first 26 user-defined keywords) are preserved during the conversion. The generated e-mail filenames include the Maildir++ extensions S=<size> and W=<vsize> (which are used by Dovecot for better performance). Optionally, Maildir++ maildirsize files are created.


Within the specified PATHs, any occurrence of %u will be replaced by the current user name, any occurrence of %nu will be replaced by the n'th character of that user name, any occurrence of %h will be replaced by Cyrus' directory ``hash'' character for that user name (i.e., %h is equivalent to %1u if the first character of the user name is a lowercase letter), and any occurrence of %x will be replaced by Cyrus' ``fulldirhash'' character for that user name. However, within the specified --cyrus-quota PATH (if any), these replacements will only be done if the --cyrus-quota-format VERSION is set to 1.

The default settings can be found (and modified) at the top of the cyrus2dovecot script.

-C, --cyrus-inbox=PATH
Use this PATH to the user's INBOX folder in Cyrus.

-c, --dovecot-crlf
Store e-mails with CR+LF instead of plain LF. This flag should be specified if the mail_save_crlf option is set to yes in the Dovecot configuration.

-D, --dovecot-inbox=PATH
Use this PATH to the user's INBOX folder in Dovecot.

-d, --debug
Print information which is usually only useful for debugging to the standard output.

-E, --edit-foldernames=SUBSTITUTION
Apply the specified SUBSTITUTION to the name of each Maildir++ folder and subscription using Perl code such as eval('$name=~'.$substitution), where $name holds either the string INBOX (which denotes the main Maildir) or the full Maildir++ folder name (e.g., .sub.folder), and $substitution holds the specified SUBSTITUTION. The resulting $name will be used as the Maildir++ folder's name. This option may be specified multiple times, in which case each of the SUBSTITUTIONs will be applied to each Maildir++ folder name in the order specified on the command line. Note that while Dovecot stores the subscribed folder names without the leading ``.'' of Maildir++ subfolders, cyrus2dovecot adds a leading ``.'' to each subscribed subfolder name before applying the specified SUBSTITUTION(s) and removes it afterwards (if it still exists) in order to simplify the matching.

-F, --dovecot-uidlist-format=VERSION
Create the dovecot-uidlist files using this format VERSION. For Dovecot releases older than 1.0.2, VERSION 1 must be specified; otherwise, VERSION 3 can be used.

-H, --dovecot-host=NAME
Use this host NAME for the Maildir++ e-mail file's basename.

-h, --help
Print usage information to the standard output and exit.

-m, --dump-meta
Print a dump of the data structure which holds the metadata gathered from scanning the Cyrus folders of a user to the standard output.

-N, --default-quota=BYTES
Create a Maildir++ maildirsize file for each user, and set the quota limit to the specified number of BYTES unless --cyrus-quota is also specified, in which case a user-specific quota would override the --default-quota limit. Specifying 0 BYTES disables the creation of maildirsize files unless --cyrus-quota is also specified.

-O, --cyrus-quota-format=VERSION
Expect the quota database file specified via --cyrus-quota to be present in this format VERSION, where VERSION 1 denotes the ``quotalegacy'' format and VERSION 2 denotes the ``skiplist'' or the ``flat'' text format (cyrus2dovecot will autodetect which of those two formats is used if VERSION 2 is specified). This option is ignored if --cyrus-quota is not specified.

-Q, --cyrus-quota=PATH
Use this PATH to the quota database file in Cyrus, and create a Maildir++ maildirsize file for each user whose quota limit is found in that file.

-q, --quiet
Suppress the line usually printed to the standard output for each user whose e-mails were successfully converted. Error messages, if any, will still be printed to the standard error output.

-S, --cyrus-seen=PATH
Use this PATH to the user's seen database file in Cyrus. If cyrus.seen is specified as the PATH, cyrus2dovecot expects an old-style cyrus.seen file in every Cyrus folder.

-U, --cyrus-sub=PATH
Use this PATH to the user's subscription database file in Cyrus.

-v, --version
Print version information to the standard output and exit.


cyrus2dovecot exits 0 on success. If a non-fatal error occurs, cyrus2dovecot prints a message to the standard error output and then tries to convert the e-mails of the remaining users (if any), but it exits >0 regardless of whether or not those conversions succeed. If a fatal error occurs, cyrus2dovecot exits >0 immediately.


Given that the default settings specified at the top of the cyrus2dovecot script are correct and that /tmp/users holds the names of all users whose e-mails should be converted (one per line), the following command would convert all e-mails of those users from Cyrus to Dovecot:

		cyrus2dovecot < /tmp/users

Given that the path to the INBOX in Cyrus is /var/spool/imap/user/%u (where %u denotes the user name), that Cyrus stores the seen and subscription databases within the directory /var/imap/user/%h, and that Cyrus stores ``quotalegacy'' files within the directory /var/imap/quota/%h (where %h denotes Cyrus' directory ``hash'' character for that user name, respectively), the following command would convert all e-mails of the users ``bill'' and ``george'' from Cyrus to Dovecot, and the result would be stored below /tmp/dovecot (including maildirsize files for both users if their quota limits are found):

		cyrus2dovecot --cyrus-inbox /var/spool/imap/user/%u     \
			      --cyrus-seen /var/imap/user/%h/%u.seen    \
			      --cyrus-sub /var/imap/user/%h/%u.sub      \
			      --cyrus-quota /var/imap/quota/%h/user.%u  \
			      --cyrus-quota-format 1                    \
			      --dovecot-inbox /tmp/dovecot/%u/Maildir   \
			      bill george

A script such as the following could be used in order to convert all e-mails of all users (of course, the pathnames and the desired quota limit may have to be adjusted, and if the hashimapspool option is enabled in the Cyrus configuration, /? must be appended to the $in path):

		in=/var/spool/imap/user         # Cyrus INBOXes.
		db=/var/imap/user/?             # Cyrus seen/subscription files.
		out=/tmp/dovecot                # Dovecot Maildirs.
		log=/tmp/conversion.log         # Log of successful conversions.
		err=/tmp/error.log              # Log of conversion errors.
		quota=2147483648                # 2 GiB quota (for maildirsize).
		for u in `find $in/. \! -name . -prune -exec basename \{\} \;`
			cyrus2dovecot --cyrus-inbox $in/$u              \
				      --cyrus-seen $db/$u.seen          \
				      --cyrus-sub $db/$u.sub            \
				      --default-quota $quota            \
				      --dovecot-inbox $out/$u/Maildir   \
				      $u 2>&1 >>$log | tee -a $err >&2

In order to create all folders (except for the INBOX) as subfolders of the INBOX in Dovecot, the following argument could be added to the cyrus2dovecot command line:

		--edit-foldernames 's/^\./.INBOX./'

Cyrus transparently replaces any ``.'' character in folder names with a ``^'' character. Dovecot supports ``.'' characters in Maildir++ folder names if the ``listescape'' plugin is used, which replaces any ``.'' character in folder names with the string ``\2e''. The following argument could be added to the cyrus2dovecot command line in order to replace any ``^'' character in Cyrus folder names with ``\2e'' for the Maildir++ folder name:

		--edit-foldernames 's/\^/\\2e/g'

Dovecot 1.1 and newer support using folders such as Maildir/sub/folder (as opposed to Maildir/.sub.folder) if :LAYOUT=fs was added to the mail_location in the Dovecot configuration. The following cyrus2dovecot arguments could be specified in order to create such folders by removing the leading dot from Maildir++ subfolder names and then substituting any following dots with slashes:

		--edit-foldernames 's/^\.//'    \
		--edit-foldernames 's/\./\//g'

If the seen states, subscriptions, or quotas are stored in Berkeley databases, they must first be converted for cyrus2dovecot using a command such as the following:

		cvt_cyrusdb /var/imap/user/b/bill.seen berkeley \
			    /tmp/imap/user/b/bill.seen skiplist


cyrus2dovecot assumes that the user has no e-mails in Dovecot yet and that neither his Cyrus folders nor his Dovecot folders will be accessed by another process during the conversion.

If %nu is specified within any PATH on the command line, all user names must have a length of at least n characters. Otherwise, cyrus2dovecot will die with an exception.

If folder name substitutions are specified via --edit-foldernames, the resulting Maildir++ folder names must be unique.


Cyrus' seen and subscription databases must be present either in the ``skiplist'' format or in the ``flat'' text format, and Cyrus' quota database(s) (if any) must be present either in one of those formats or in the ``quotalegacy'' format, as cyrus2dovecot doesn't support Berkeley databases. However, Berkeley databases can be converted to one of the supported formats using cvt_cyrusdb(8), see the EXAMPLES.

In maildirsize files created by cyrus2dovecot, no limit for the number of messages is specified (as such a limit does not seem useful).

Cyrus' ACL settings are not converted.


cyrus2dovecot is supposed to work with all Cyrus releases up to (at least) version 2.3.x. So far, it has been tested with Cyrus 1.4, 2.1.18, 2.2.12, and 2.3.12p2.


Other tools for converting e-mails from Cyrus to Dovecot can be found at http://wiki.dovecot.org/Migration/Cyrus.


Written by Holger Weiß <holger@ZEDAT.FU-Berlin.DE> at Freie Universität Berlin, Germany, Zentraleinrichtung für Datenverarbeitung (ZEDAT).


Copyright (c) 2008 Freie Universität Berlin. All rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic(1). This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.


		Revision 1.2  2008/09/24 09:52:33  holger
		Message seen states are now parsed more efficiently with regard
		to performance and memory usage.  Apart from that, minor code
		cleanups have been applied.
		Revision 1.1  2008/09/22 08:36:44  holger
		Initial release.
© ZEDAT, Freie Universität Berlin