Иногда возникает необходимость переезда с одного почтового сервера на другой, перенос всех почтовых сообщений может стать головной болью.

Есть один не слишком мудреный способ синхронизировать два почтовых ящика на разных почтовых сервисах через протокол imap, используя imapsync.

Подготовка

Для начала, нужно подключить репозиторий, содержащий нужные установочные пакеты (подробнее о подключении сторонних репозиториев):

В CentOS 5:

wget http://dl.fedoraproject.org/pub/epel/5/x86_64/epel-release-5-4.noarch.rpm
wget http://rpms.famillecollet.com/enterprise/remi-release-5.rpm
rpm -Uvh remi-release-5*.rpm epel-release-5*.rpm

В CentOS 6:

wget http://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
wget http://rpms.famillecollet.com/enterprise/remi-release-6.rpm
rpm -Uvh remi-release-6*.rpm epel-release-6*.rpm
Now, use yum to install imapsync. It will automagically install all of the deps.

Сама установка проста и не отличается от установки других пакетов:

yum install imapsync

Теперь ознакомимся с возможностями утилиты:

[root@nix-tips.ru ~]# imapsync --help

usage: /usr/bin/imapsync [options]

Several options are mandatory.

--dry : Makes imapsync doing nothing, just print what would
be done without --dry.

--host1 <string> : Source or "from" imap server. Mandatory.
--port1 <int> : Port to connect on host1. Default is 143.
--user1 <string> : User to login on host1. Mandatory.
--showpasswords : Shows passwords on output instead of "MASKED".
Useful to restart a complete run by just reading a log.
--password1 <string> : Password for the user1.
--host2 <string> : "destination" imap server. Mandatory.
--port2 <int> : Port to connect on host2. Default is 143.
--user2 <string> : User to login on host2. Mandatory.
--password2 <string> : Password for the user2.

--passfile1 <string> : Password file for the user1. It must contain the
password on the first line. This option avoids to show
the password on the command line like --password1 does.
--passfile2 <string> : Password file for the user2. Contains the password.
--domain1 <string> : Domain on host1 (NTLM authentication).
--domain2 <string> : Domain on host2 (NTLM authentication).
--authuser1 <string> : User to auth with on host1 (admin user).
Avoid using --authmech1 SOMETHING with --authuser1.
--authuser2 <string> : User to auth with on host2 (admin user).
--proxyauth1 : Use proxyauth on host1. Requires --authuser1.
Required by Sun/iPlanet/Netscape IMAP servers to
be able to use an administrative user.
--proxyauth2 : Use proxyauth on host2. Requires --authuser2.
Required by Sun/iPlanet/Netscape IMAP servers to
be able to use an administrative user

--authmd51 : Use MD5 authentification for host1.
--authmd52 : Use MD5 authentification for host2.
--authmech1 <string> : Auth mechanism to use with host1:
PLAIN, LOGIN, CRAM-MD5 etc. Use UPPERCASE.
--authmech2 <string> : Auth mechanism to use with host2. See --authmech1
--ssl1 : Use an SSL connection on host1.
--ssl2 : Use an SSL connection on host2.
--tls1 : Use an TLS connection on host1.
--tls2 : Use an TLS connection on host2.
--timeout <int> : Connections timeout in seconds. Default is 120.
0 means no timeout.

--folder <string> : Sync this folder.
--folder <string> : and this one, etc.
--folderrec <string> : Sync this folder recursively.
--folderrec <string> : and this one, etc.

--folderfirst <string> : Sync this folder first. --folderfirst "Work"
--folderfirst <string> : then this one, etc.
--folderlast <string> : Sync this folder last. --folderlast "[Gmail]/All Mail"
--folderlast <string> : then this one, etc.

--include <regex> : Sync folders matching this regular expression
Blancs like in "foo bar" have to be written "foo\ bar"
--include <regex> : or this one, etc.
in case both --include --exclude options are
use, include is done before.
--exclude <regex> : Skips folders matching this regular expression
Several folders to avoid:
--exclude 'fold1|fold2|f3' skips fold1, fold2 and f3.
--exclude <regex> : or this one, etc.
--regextrans2 <regex> : Apply the whole regex to each destination folders.
--regextrans2 <regex> : and this one. etc.
When you play with the --regextrans2 option, first
add also the safe options --dry --justfolders
Then, when happy, remove --dry, remove --justfolders.
Have in mind that --regextrans2 is applied after prefix
and separator inversion.

--tmpdir <string> : Where to store temporary files and subdirectories.
Will be created if it doesn't exist.
Default is system specific, Unix is /tmp but
it's often small and deleted at reboot.
--tmpdir /var/tmp should be better.
--pidfile <string> : The file where imapsync pid is written.
--pidfilelocking : Abort if pidfile already exists. Usefull to avoid
concurrent transfers on the same mailbox.

--prefix1 <string> : Remove prefix to all destination folders
(usually INBOX. or INBOX/ or an empty string "")
you have to use --prefix1 if host1 imap server
does not have NAMESPACE capability, all other
cases are bad.
--prefix2 <string> : Add prefix to all host2 folders. See --prefix1
--sep1 <string> : Host1 separator in case NAMESPACE is not supported.
--sep2 <string> : Host2 separator in case NAMESPACE is not supported.

--disarmreadreceipts : Disarms read receipts (host2 Exchange issue)
--regexmess <regex> : Apply the whole regex to each message before transfer.
Example: 's/\000/ /g' # to replace null by space.
--regexmess <regex> : and this one.
--regexmess <regex> : and this one, etc.
--regexflag <regex> : Apply the whole regex to each flags list.
Example: 's/"Junk"//g' # to remove "Junk" flag.
--regexflag <regex> : and this one, etc.

--delete : Deletes messages on host1 server after a successful
transfer. Option --delete has the following behavior:
it marks messages as deleted with the IMAP flag
\Deleted, then messages are really deleted with an
EXPUNGE IMAP command.
--delete2 : Delete messages in host2 that are not in
host1 server. Useful for backup or pre-sync.
--delete2duplicates : Delete messages in host2 that are duplicates.
Works only without --useuid since duplicates are
detected with header part of each message.
--delete2folders : Delete folders in host2 that are not in host1 server.
For safety, first try it like this (it is safe):
--delete2folders --dry --justfolders --nofoldersizes
--delete2foldersonly <regex>: Deleted only folders matching regex.
Example: --delete2foldersonly "/^Junk$|^INBOX.Junk$/"
--delete2foldersbutnot <regex>: Do not delete folders matching regex.
Example: --delete2foldersbutnot "/Tasks$|Contacts$|Foo$/"
--noexpunge : Do not expunge messages on host1.
Expunge really deletes messages marked deleted.
Expunge is made at the beginning, on host1 only.
Newly transferred messages are also expunged if
option --delete is given.
No expunge is done on host2 account (unless --expunge2)
--expunge1 : Expunge messages on host1 after messages transfer.
--expunge2 : Expunge messages on host2 after messages transfer.
--uidexpunge2 : uidexpunge messages on the host2 account
that are not on the host1 account, requires --delete2

--syncinternaldates : Sets the internal dates on host2 same as host1.
Turned on by default. Internal date is the date
a message arrived on a host (mtime).
--idatefromheader : Sets the internal dates on host2 same as the
"Date:" headers.

--maxsize <int> : Skip messages larger (or equal) than <int> bytes
--minsize <int> : Skip messages smaller (or equal) than <int> bytes
--maxage <int> : Skip messages older than <int> days.
final stats (skipped) don't count older messages
see also --minage
--minage <int> : Skip messages newer than <int> days.
final stats (skipped) don't count newer messages
You can do (+ are the messages selected):
past|----maxage+++++++++++++++>now
past|+++++++++++++++minage---->now
past|----maxage+++++minage---->now (intersection)
past|++++minage-----maxage++++>now (union)

--search <string> : Selects only messages returned by this IMAP SEARCH
command. Applied on both sides.
--search1 <string> : Same as --search for selecting host1 messages only.
--search2 <string> : Same as --search for selecting host2 messages only.
--search CRIT equals --search1 CRIT --search2 CRIT

--exitwhenover <int> : Stop syncing when total bytes transferred reached.
Gmail per day allows 2500000000 down 500000000 upload.

--maxlinelength <int> : skip messages with a line length longer than <int> bytes.
RFC 2822 says it must be no more than 1000 bytes.

--useheader <string> : Use this header to compare messages on both sides.
Ex: Message-ID or Subject or Date.
--useheader <string> and this one, etc.

--subscribed : Transfers subscribed folders.
--subscribe : Subscribe to the folders transferred on the
host2 that are subscribed on host1. On by default.
--subscribe_all : Subscribe to the folders transferred on the
host2 even if they are not subscribed on host1.

--nofoldersizes : Do not calculate the size of each folder in bytes
and message counts. Default is to calculate them.
--nofoldersizesatend : Do not calculate the size of each folder in bytes
and message counts at the end. Default is on.
--justfoldersizes : Exit after having printed the folder sizes.

--syncacls : Synchronises acls (Access Control Lists).
--nosyncacls : Does not synchronize acls. This is the default.
Acls in IMAP are not standardized, be careful.

--usecache : Use cache to speedup.
--nousecache : Do not use cache. Caveat: --useuid --nousecache creates
duplicates on multiple runs.
--useuid : Use uid instead of header as a criterium to recognize
messages. Option --usecache is then implied unless
--nousecache is used.

--debug : Debug mode.
--debugcontent : Debug content of the messages transfered.
--debugflags : Debug flags.
--debugimap1 : IMAP debug mode for host1. imap debug is very verbose.
--debugimap2 : IMAP debug mode for host2.
--debugimap : IMAP debug mode for host1 and host2.

--version : Print software version.
--noreleasecheck : Do not check for new imapsync release (a http request).
--releasecheck : Check for new imapsync release (a http request).
--justconnect : Just connect to both servers and print useful
information. Need only --host1 and --host2 options.
--justlogin : Just login to both host1 and host2 with users
credentials, then exit.
--justfolders : Do only things about folders (ignore messages).

--help : print this help.

Example: to synchronize imap account "foo" on "imap.truc.org"
to imap account "bar" on "imap.trac.org"
with foo password "secret1"
and bar password "secret2"

/usr/bin/imapsync \
--host1 imap.truc.org --user1 foo --password1 secret1 \
--host2 imap.trac.org --user2 bar --password2 secret2

Here is a [linux] system (Linux nix-tips.ru 3.10.0-123.13.1.el7.x86_64 #1 SMP Tue Dec 9 23:06:09 UTC 2014 x86_64)
With perl 5.16.3 Mail::IMAPClient 3.34
$Id: imapsync,v 1.592 2014/05/22 10:03:17 gilles Exp gilles $
New imapsync release 1.607 available

Homepage: http://imapsync.lamiral.info/

Займемся делом

Пойдем от простого к сложному. Сначала надо понять, как перенести содержимое одного почтового ящика. Затем нужно организовать пакетный перенос ящиков со старого почтового сервера на новый.

Синхронизация одного ящика

Исходные данные:

• Старый сервер: mailserver1.ru
• Новый сервер: mailserver2.ru
• Имя пользователя: test@nix-tips.ru
• Старый пароль: pa$$word
• Новый пароль: pa$$word

Синхронизация осуществляется командой:

[root@nix-tips.ru ~]# imapsync \
--host1 mailserver1.ru --user1 test@nix-tips.ru --password1 pa$$word \
--host2 mailserver2.ru --user2 test@nix-tips.ru --password2 pa$$word

Готово!

Почтовый ящик test@nix-tips.ru теперь на обоих серверах содержит одинаковые письма.

Пакетная синхронизация по imap

Нам понадобится список ящиков в текстовом файле. Назовем его emails-list.txt:

user1@nix-tips.ru;user1pa$$;user1@nix-tips.ru;user1pa$$
user2@nix-tips.ru;user2pa$$;user2@nix-tips.ru;user2pa$$
user3@nix-tips.ru;user3pa$$;user3@nix-tips.ru;user3pa$$
user4@nix-tips.ru;user4pa$$;user4@nix-tips.ru;user4pa$$
user5@nix-tips.ru;user5pa$$;user5@nix-tips.ru;user5pa$$

Список сохранить рядом со скриптом sync_imap_batch.sh:

#!/bin/sh

mkdir -p LOG

{ while IFS=';' read u1 p1 u2 p2
do
{ echo "$u1" | egrep "^#" ; } > /dev/null && continue
NOW=`date +%Y_%m_%d_%H_%M_%S`
echo syncing to user "$u2"
imapsync --host1 mailserver1.ru --user1 "$u1" --password1 "$p1" \
--host2 mailserver2.ru --user2 "$u2" --password2 "$p2" \
> LOG/log_${u2}_$NOW.txt 2>&1
done
} < file.txt

После запуска скрипта:

./sync_imap_batch.sh

И небольшого ожидания, мы получим полное соответствие содержимого почтовых ящиков нового сервера старому.