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62
FAQ.d/FAQ.Domino.txt Normal file
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#!/bin/cat
$Id: FAQ.Domino.txt,v 1.2 2015/03/26 04:24:17 gilles Exp gilles $
======================================================================
Domino specific issues and solutions
======================================================================
======================================================================
Q. From Domino Notes to xxx
On Windows use:
imapsync.exe ... --sep2 "\\" --prefix2 ""
On Unix use:
imapsync ... --sep2 '\\' --prefix2 ''
======================================================================
Q. From xxx to Domino Notes
For Domino anywhere with imapsync.exe on Windows use:
imapsync.exe ... ^
--sep2 "\\" --prefix2 "" ^
--regextrans2 "s,^INBOX\\(.*),$1,"
Explanation: Domino doesn't accept INBOX subfolders.
If you want to sync the complete host1 mailbox in a subfolder called OLDBOX use:
imapsync.exe ... ^
--sep2 "\\" --prefix2 "" ^
--regextrans2 "s,(.*),OLDBOX\\$1," --justfolders --dry
If the output is correct for you then remove --dry and have a run.
Verify the folder hierarchy is good on host2 then remove --justfolders to
sync the messages.
For Domino with imapsync and Domino on Linux:
(Thanks to Zafer)
R. We've migrated about 5000 users from cyrus to lotus domino 853!
Mails are being copied into the new created lotus domino mailbox
retaining the existing folder structure from the old mail database.
This means that sent mails can be found in the sent folder and
mails from the old inbox are copied into the new inbox
We also marked migrated mails with the header Migratedbyus
For Domino 853FP6 on Linux, we used this command on Unix:
imapsync \
--host1 hhh1 --user1 uuu1 --password1 ppp1 \
--host2 hhh2 --user2 uuu2 --password2 ppp2 \
--exclude "^INBOX/Trash" --exclude 'Junk|Drafts' \
--regextrans2 's#^INBOX/Sent$#^Sent#' \
--prefix2 "" --sep2 "\/" \
--regexmess 's{\A(.*?(?! ^$))^Date:(.*?)$}{$1Migratedbyus:$2\nx-MailDate:$2}gxms'
======================================================================

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FAQ.d/FAQ.Dovecot.txt Normal file
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#!/bin/cat
$Id: FAQ.Dovecot.txt,v 1.1 2015/03/23 00:16:43 gilles Exp gilles $
=======================================================================
Dovecot specific issues and solutions
=======================================================================
======================================================================
Q. How to migrate to Dovecot with an admin/MasterUser account?
R. Dovecot uses the same syntax as uw-imap
imapsync ... --user2="loginuser*admin_user" --password2 "admin_user_password"
To setup a Dovecot MasterUser see
http://wiki2.dovecot.org/Authentication/MasterUsers
======================================================================

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FAQ.d/FAQ.Exchange.txt Normal file
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#!/bin/cat
$Id: FAQ.Exchange.txt,v 1.2 2015/03/16 15:11:32 gilles Exp gilles $
=======================================================================
Exchange 20xx and Office365 specific issues and solutions
=======================================================================
=======================================================================
Q. From XXX to Exchange 2010/2013 or Office365
R. Here is a command line resume that solves most encountered issues when
migrating to Exchange or Office365. To understand or change the
details you have to read next Q/R sections.
On Windows:
imapsync ... ^
--maxsize 10000000 ^
--maxlinelength 9900 ^
--regexflag "s/\\Flagged//g" ^
--disarmreadreceipts
On Unix:
imapsync ... \
--maxsize 10000000 \
--maxlinelength 9900 \
--regexflag "s/\\Flagged//g" \
--disarmreadreceipts
=======================================================================
Q. From XXX to Exchange 2013 or Office365 read receipts are all
resent again after a sync. Even for old messages. How can I fix that?
R. imapsync can remove the header containing this read receipt request.
On Unix or Windows use:
imapsync ... --disarmreadreceipts
Since read receipts should be sent for unseen messages that will go
to a seen state after the migration, you could be strict and apply
the regex only to seen messages.
Selecting seen message can be done with:
imapsync ... --search1 "SEEN" --disarmreadreceipts
Of course a second run has to be run without the --disarmreadreceipts
for unseen messages:
imapsync ... --search1 "UNSEEN"
If fact --disarmreadreceipts is just an option equivalent to:
--regexmess 's{\A(.*?(?! ^$))^Disposition-Notification-To:(.*?)$}{$1X-Disposition-Notification-To:$2}igxms'
That regex changes the header Disposition-Notification-To. It prefixes
it with an X- so that it becomes inactive.
Disposition-Notification-To: blabla
becomes
X-Disposition-Notification-To: blabla
Thanks to David Karnowski for pointing and solving this issue.
=======================================================================
Q. From XXX to Exchange 2010/2013 or Office365 I get this error message
sometimes: "BAD Command Argument Error 11"
R. This error message comes from Exchange IMAP server when it
encounters any problem. Most of the time it is one of the following:
* Some messages are bigger than the size limit. 10 MB by default
on Exchange. It can be upped by configuration for Exchange.
If you can't configure this limit then use option
--maxsize 10000000 for 10 MB, change it if needed) to tell
imapsync to skip those messages.
This value is 25 MB by default for Office365 --maxsize 25000000
imapsync ... --maxsize 10000000 # 10 MB for Exchange
imapsync ... --maxsize 25000000 # 25 MB for Office365
* Quota reached. The whole account is full.
It can be upped by configuration.
* Some messages have some lines too long. Use option --maxlinelength
to skip messages whose max line length is over a number of bytes.
--maxlinelength 1000 is a RFC2822 must but most server support
higher values. Exchange supports 9900:
imapsync ... --maxlinelength 9900
Have also in mind that Exchange closes the connection after 10 errors
encountered so you might also see "BYE Connection closed" errors from
Exchange, which means Exchange leaves the session and say goodbye,
come back later. Rerun a sync then.
=======================================================================
Q. From XXX to Exchange 2010 or 2013 or Office365 the flag Flagged does
not seem to be well synced.
R. Use the following trick. Run imapsync twice, one with --regexflag
and one without, like this:
1) imapsync ... --regexflag "s/\\Flagged//g"
2) imapsync ...
You can add --debugflags if you want to see what imapsync gets and
does in details with flags.
The magic of this trick is on ignoring the \Flagged flag on the first
sync and setting it on the second sync, with STORE instead of APPEND.
This Exchange bug seems that Exchange gets and sets well the Flagged
flag with APPEND in IMAP but then it forgets it with other protocols;
With STORE it sets and gets the "\Flagged" flag everywhere.
Thanks to Dave Murray and Simon Savva for reporting and solving
this issue.
======================================================================
Q. How to migrate from or to Exchange 2007/2010 with an
admin/authuser account?
R. The tricks comes from Michele Marcionelli and Benjamin Priestman:
This doesn't work:
imapsync ... --user2 user2 --authuser2 admin2 --password2 adminpassword2 ...
This might works:
imapsync ... --user2 "domain\admin2\user2" --password2 adminpassword2 ...
or
imapsync ... --user2 "admin2@domain\user2" --password2 adminpassword2 ...
where "domain" is set be the user's UPN in Active Directory
or the NETBIOS or DNS name of the domain.
The exact format might vary depending on local configuration and you
should experiment with the different formats.
PLAIN authentication is the only way to go with --authuser1 for now.
So don't use --authmech1 SOMETHING with --authuser1 admin_user,
it will not work.
Same behavior with the --authuser2 option.
A little note from Michael Scherer.
The previous workaround in the FAQ seems to be obsolete.
I can confirm that
imapsync ... --host2 exchange_server \
--authuser2 admin@domain --user2 user_alias
is working without any glitches, running Exchange 2010 SP2 here.
Explanation, Exchange knows a) about a username
and b) about a mailNickname which can be different to the username.
As it seems you need to use the mailNickname (e.g. alias) defined
for user2, not the username itself.
http://blogs.technet.com/b/exchange/archive/2004/03/31/105275.aspx
A little note from John Becker.
After you pointed out that I had issues with authorization, I realized that
as an admin user I don't have all the rights on the mailboxes.
So I added myself to the user mailbox with full rights.
I also changed the login type on the Exchange CAS to type 1, plain text.
The command that I used for imapsync is:
imapsync ... ^
--host2 exchange-server ^
--user2 "windows-domain\admin-user\aaaa" ^
--password2 admin-password ...
======================================================================
Q. How to migrate from or to Office 365 with an admin/authuser account?
Note from Yago Torres Fernandez:
(a working command using admin/authuser on host2 Office 365)
imapsync ... --authuser2 user_admin@domain.com --user2 user_to_be_migrated@domain.com ^
--password2 XXXX --ssl2 --exclude "Shared Folders" ^
--regextrans2 "s#Trash$#Papelera#" --regextrans2 "s#^Deleted Items$#Papelera#"
but previous in Office365 you must do something like that, using powershell:
Add-MailboxPermission -identity user_to_be_migrated@domain.com -user user_admin@domain.com -accessrights fullaccess -inheritancetype all
PLAIN authentication is the only way to go with --authuser1 for now.
So don't use --authmech1 SOMETHING with --authuser1 admin_user,
it will not work.
Same behavior with the --authuser2 option.
======================================================================
Q. How to migrate from or to Exchange 2003 with an admin/authuser
account?
R. Thomas Edgar wrote the following
In case you can glean something from this snippet which allowed us
to migrate from Exchange 2003 t0 Cyrus Imap 2.4 (you would reverse
the flow to go the other way):
imapsync --dry --host1 ExchangeServer.mycompany.com \
--user1 Some.User@mycompany.com --authuser1 ExchangeAdminAccount \
--proxyauth1 --password1 '$pass_with_dollars$' \
--host2 cyrusimapbackend.mycompany.com \
--user2 SameOrDiffererentUser@mycompany.com \
--authuser2 CyrusAdminAccount --password2 CyrusAdminPassword
We also needed to:
- Ensure the Exchange Admin Acct had IMAP4 enabled in it's
profile (it initially didn't!)
- Ensure the Some.User Exchange Acct had IMAP4 enabled
in it's profile (it initially didn't!)
- Add the CyrusAdminAccount to admins line in /etc/imapd.conf
- Give CyrusAdminAccount lrswipkxtecda to the Cyrus Imap account
being migrated to (- or in your case, from)
In case you are not aware:
- It will prompt for a password if you don't supply it
- the domain part of the fully-qualified email could be
omitted in our case
- Use --debugimap when testing initial connectivity, if necessary
=======================================================================
Q. Couldn't create folder [trash] from [INBOX.trash]:
588 NO Mailbox already exists.
R. Some servers take care about character case in folder names,
some servers do not, like Exchange. Since non-respecting case
can merge two different folders into one then imapsync respects case.
For example, if a host1 server has a folder name called "trash"
and the host2 server already has a folder "Trash" or "TRASH"
then imapsync will try to create the folder "trash" on host2,
because trash and Trash are different strings. But if host2
does not respect character case it will consider folder "trash"
already exists and will say it, that's the error message
reported by imapsync: "Mailbox already exists", message coming
from the server.
The folder creation fails but messages are well transferred in
so take a look at this warning, understand why it happens
and it should be fine most of the time.
To avoid this warning use --regextrans2 to map the folder names
imapsync ... --regextrans2 "s/^trash$/Trash/"
If there are two folders Trash and trash on host1 then both
will be merge into only one Trash folder on host2.
In case option --delete2 is used the regextans2 above becomes
mandatory, otherwise imapsync will sync messages from the
first Trash and then delete them when syncing trash.
======================================================================
Q. Migrating to Exchange 201O, messages get date of the transfer,
this is bad for sorting and listing.
R1. Be sure to have at least Exchange 2010 SP2 Rollup 5
http://www.tribalchicken.com.au/15-technical/29-imapsync-exchange2010
R2. See also the Outlook side (thanks to Martin Hochreiter for this solution)
http://www.howto-outlook.com/faq/archivenotworking.htm
by changing Archive to sent/receive date
It's often shorter to change one server than thousands clients
so R1 might be easier to do.
======================================================================
Q. From any to Exchange2007
Several problems:
- Big messages: increase the "send- and receive-connector"
in exchange2007 to 40 MB.
R. 2 solutions
R1. With imapsync (only partial success)
--skipheader 'Received' \
--regexmess 's{\A(.*?(?!^$))^Date:(.*?)$}{$1Date:$2\nReceived: From; $2}gxms'
Any user having time to spend to debug Exchange2007 with imapsync
is welcome.
R2. Other solution
Two users succeeded by using "MS Transporter Suite" (which is closed
expensive non-free software).
======================================================================
Q. From Microsoft Exchange 2000 IMAP4rev1 server version 6.0.6487.0.
R. imapsync ... \
--prefix1 INBOX.
=======================================================================

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#!/bin/cat
$Id: FAQ.Gmail.txt,v 1.1 2015/03/26 08:12:20 gilles Exp gilles $
======================================================================
Imapsync with Gmail
======================================================================
=======================================================================
Q. Synchronizing from XXX to Gmail
R. There are some details to get the special [Gmail] sub-folders
right. Here's an example of migrating an old "Sent" folder to
Gmail's structure:
imapsync --host1 mail.oldhost.com \
--user1 my_email@oldhost.com \
--password1 password \
--host2 imap.gmail.com \
--user2 my_email@gmail.com \
--password2 password \
--ssl2 \
--exitwhenover 500000000 \
--maxsize 25000000 \
--expunge1 \
--addheader \
--exclude "\[Gmail\]$" \
--regextrans2 "s/[ ]+/_/g" \
--regextrans2 "s/[\^]/_/g" \
--regextrans2 "s/['\"\\\\]/_/g" \
--regextrans2 "s,^Sent$,[Gmail]/Sent Mail,"
Explanations:
--ssl2 is mandatory since Gmail only supports imap ssl connections.
--exitwhenover 500000000 option is here to avoid locking when
transfers exceed maximum limit.
See http://support.google.com/a/bin/answer.py?hl=en&answer=1071518
--exitwhenover is not mandatory in the sense you may be able to
use an upper value than 500 MB without disconnections; I don't
know the hard value, it seems to vary, so just have some tries
and report me what you discover in case you detect something.
--maxsize 25000000 is mandatory since Gmail limits messages size
up to 25 MB. This value increases over time, it was 10 MB some
years ago so you can try higher values. The Gmail page about
this limit is https://support.google.com/mail/answer/6584
--expunge1 is optional. It deletes messages marked \Deleted on host1.
Imapsync syncs messages with all their flags, Gmail takes the messages
marked \Deleted but deletes or moves them just after.
Option --expunge1 really removes messages marked \Deleted on host1
so they are not synced at all.
The --addheader option is there because "Sent" folder messages
sometimes lack the "Message-Id:" and "Received:" headers needed
by imapsync to identify messages (only when --useuid is not used).
So option --addheader adds a "Message-Id" header consisting of
the imap UID of the message on the host1 folder, like
"Message-Id: 12345@imapsync".
--exclude "\[Gmail\]$" is there to avoid a small examine/select error:
"Could not examine: 43 NO [NONEXISTENT] Unknown Mailbox: [Gmail]
(now in authenticated state) (Failure)".
--regextrans2 "s/[ ]+/_/g" is there to convert blank characters not
accepted by gmail to character _ underscore. In fact only leading
and trailing blank characters are problems with gmail, and
also successive blanks ending with the IMAP error
"NO [CANNOT] Folder contains excess whitespace (Failure)"
If you want to change only leading and trailing blank characters
then use instead:
--regextrans2 "s,(/|^) +,\$1,g" --regextrans2 "s, +(/|$),\$1,g"
On Windows, in the previous example containing \$1 you have to
replace the two \$1 by $1 (remove the \ before $1).
--regextrans2 "s/[\^]/_/g" is mandatory. It converts, since
not accepted by gmail, character ^ to character _ underscore.
--regextrans2 "s/['\"\\\\]/_/g" is optional. It converts
characters ' or " or \ to character _ underscore.
--regextrans2 "s,^Sent$,[Gmail]/Sent Mail," is to transform the
folder name "Sent" and adapt it to Gmail "Sent Mail" folder.
If you're using a different language in Gmail you might adapt
this example with the folder name translated, an example in French:
imapsync ...
--regextrans2 "s,^Messages envoy&AOk-s$,[Gmail]/Messages envoy&AOk-s," \
You can add --folder "INBOX.Sent" in the example in case
you want to sync only the "Sent" folder.
You can select folders exported to imap within the gmail preferences,
unselect some "System labels", depending on your needs.
The "All Mail" archive pseudo-folder should be updated automatically.
=======================================================================
Q. Some of the folders are getting created with [IMAP] prefix on Google
side. How to stop creating folder with this prefix?
Any switch we can use? e.g. [IMAP]/Archive
R. No switch in imapsync since [IMAP]/ prefix is done by Gmail,
it might be configurable with Gmail parameters.
=======================================================================
Q. Synchronizing from Gmail to XXX
R. Gmail needs SSL
./imapsync \
--host1 imap.gmail.com \
--user1 gilles.lamiral@gmail.com \
--password1 gmailsecret \
--host2 localhost
--user2 tata \
--password2 tatasecret \
--ssl1 \
--exitwhenover 2500000000 \
--useheader="X-Gmail-Received" \
--useheader "Message-Id" \
--skipcrossduplicates \
--folderfirst "Work" \
--folderfirst "Friends" \
--folderlast "CanWait" \
--folderlast "[Gmail]/All Mail"
Explanations:
--ssl1 is mandatory since Gmail only supports imap ssl connections.
--exitwhenover 2500000000 option is here to avoid locking when
transfers exceed maximum limit.
See http://support.google.com/a/bin/answer.py?hl=en&answer=1071518
--exitwhenover is not mandatory in the sense you may be able to
use an upper value than 2.5 GB without disconnections; I don't
know the hard value, it seems to vary, so just have some tries
and report me what you discover in case you detect something.
--useheader="X-Gmail-Received" --useheader "Message-Id" are not
mandatory. I use them because I found (several years ago, it may
have changed) that Gmail always adds a different header
"X-Gmail-Received:" to all messages it gets. So the identification
by imapsync can not fail using this header. "Message-Id" is there
for safety about this Gmail rule.
If your destination imap server doesn't like "[Gmail]" name, just add
option:
--regextrans2 's/\[Gmail\]/Gmail/'
You can select folders exported to imap within the gmail preferences,
for example you may unselect all "System labels".
--exitwhenover option is here to avoid locking when transfers
exceed maximum limit.
See http://support.google.com/a/bin/answer.py?hl=en&answer=1071518
--skipcrossduplicates is optional but it can save Gigabytes of hard
disk memory. Within imap protocol, Gmail presents Gmail labels as
folders, so a message labeled "Work" "ProjectX" "Urgent" ends up
in three different imap folders "Work" "ProjectX" and "Urgent"
after an imap sync. --skipcrossduplicates prevent this behavior.
An issue with --skipcrossduplicates is that the first label synced
by imapsync goes to its corresponding folder and other labels are
ignored. This way, at least you can choose what labels have the
priority by using the --folderfirst option. For example
--folderfirst "Work" will sync messages labeled "Work" before
messages labeled "CanWait" or "Urgent". By default imapsync
syncs folders (Gmail labels) using the classical alphanumeric order.
--folderlast "CanWait" will sync only messages that have the
label CanWait and only it.
--folderlast "[Gmail]/All Mail", in conjunction with option
--skipcrossduplicates, will only put in "[Gmail]/All Mail"
the messages that are not labeled at all.
=======================================================================
Q. Gmail does not really delete messages in folder [Gmail]/All Mail
What happens? What can I do?
R. It's true and explained in Gmail documentation at
https://support.google.com/mail/answer/78755?hl=en
To really remove messages in folder "[Gmail]/All Mail", they have to
be moved to the "Trash" folder and be deleted from "Trash".
=======================================================================
Q. Does imapsync have the capability to do 2 stage authentication for google.
R. No, imapsync doesn't support 2 stage authentication.
Reading https://support.google.com/mail/answer/1173270?hl=en
it looks like it can't because imapsync uses imap protocol.
So you have to follow the Google recommendation and generate an
application-specific password or normal authentication or XOAUTH.
=======================================================================
Q. Is XOAUTH2 authentication available with imapsync?
R. Yes but only on Unix systems and not really well documented. See
* http://www.linux-france.org/prj/imapsync_list/msg02129.html
* https://github.com/imapsync/imapsync/pull/25/files
=======================================================================
Q. How to use XOAUTH to globally authenticate gmail users?
The XOAUTH code and this FAQ item come from Eduardo Bortoluzzi
Thanks Eduardo!
R. The goal of OAUTH is to migrate all users from/to Google Apps
Premier Edition without knowing their passwords.
The global password is available at the Google Apps control panel,
at Advanced Tools -> Manage OAuth domain key.
./imapsync \
--host1 imap.gmail.com --ssl1 \
--user1 foo@lab3.dedal.br \
--password1 secret1 \
--authmech1 XOAUTH \
--host2 imap.gmail.com --ssl2 \
--user2 bar@lab3.dedal.br \
--password2 secret2 \
--authmech2 XOAUTH
Google Apps is a paid service, but you can try it for 30 days without any cost.
Some notes about configuring the Google Apps XOAUTH:
On "Advanced Tools > Manage OAuth domain key > Two-legged OAuth access control"
the "Allow access to all APIs" must be checked
(https://support.google.com/a/bin/answer.py?answer=162105)
OR
On "Advanced Tools > Manage third party OAuth client access",
the configured costumer key must have the scope
"https://mail.google.com/" configured
(https://support.google.com/a/bin/answer.py?answer=162106).
=======================================================================
Q. migrate email from gmail to google apps
R. Take a look at:
http://www.linux-france.org/prj/imapsync_list/msg00639.html
http://biasecurities.com/blog/2009/migrate-email-from-gmail-to-google-apps/
http://www.thamtech.com/blog/2008/03/29/gmail-to-google-apps-email-migration/

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#!/bin/cat
$Id: FAQ.Massive.txt,v 1.1 2015/03/26 05:06:27 gilles Exp gilles $
======================================================================
Imapsync for massive migrations
======================================================================
Questions answered here are:
Q. I need to migrate hundred accounts, how can I do?
Q. I have to migrate 500k users using 400 TB of disk space.
How do I proceed?
=======================================================================
Q. I need to migrate hundred accounts, how can I do?
R. If you have many mailboxes to migrate think about a little
shell program. Write a file called file.txt (for example)
containing users and passwords.
The separator used in this example is ";"
The file.txt file contains:
user001_1;password001_1;user001_2;password001_2
user002_1;password002_1;user002_2;password002_2
user003_1;password003_1;user003_2;password003_2
user004_1;password004_1;user004_2;password004_2
user005_1;password005_1;user005_2;password005_2
...
On Unix the shell program can be:
{ while IFS=';' read u1 p1 u2 p2; do
imapsync --host1 imap.side1.org --user1 "$u1" --password1 "$p1" \
--host2 imap.side2.org --user2 "$u2" --password2 "$p2" ...
done ; } < file.txt
Here is a complete Unix example nearly ready to use:
http://imapsync.lamiral.info/examples/sync_loop_unix.sh
On Windows the batch program can be:
FOR /F "tokens=1,2,3,4 delims=; eol=#" %%G IN (file.txt) DO imapsync ^
--host1 imap.side1.org --user1 %%G --password1 %%H ^
--host2 imap.side2.org --user2 %%I --password2 %%J ...
The ... can be replaced by nothing or any supplementary imapsync option.
Here is a complete Windows example nearly ready to use:
http://imapsync.lamiral.info/examples/sync_loop_windows.bat
=======================================================================
Q. I have to migrate 500k users using 400 TB of disk space.
How do I proceed?
R. Solution to this issue is two words: parallelism and measurements.
Since all 500k mailboxes are independent against each other,
they can be processed independently.
500k on 400TB is 800 MB per account on average.
No one knows in advance what is the first bottleneck. The first
bottleneck has to be determined, by measurements, not by guesses.
Once this first bottleneck is known and overcome then the next
bottleneck has to be determined and overcome too, if needed. Repeat
the process of looking for the next bottleneck and its resolution
until you estimate the transfer rates, money costs and final dates are
good enough to proceed the whole 500k/400TB migration.
Possible bottlenecks:
- IMAP servers have artificial limits. For example Gmail and Office365
have throttle limits.
- Bandwidth, on any side, especially on small Internet connexions. But
usually bandwidth is not a bottleneck.
- Memory, on any side. Monitor your system doesn't swap on disk.
- CPU, on any side. When measuring that CPU is always 100% during a
transfer then it's useless to add imapsync processus on that host.
- I/O on disks. A classical one always forgotten. Unlike CPU and RAM
Input/Output performances don't improve very much as time goes on.
- Number of hosts available to run imapsync processes.
- Imapsync itself.
- Errors management.
- MX domains, DNS.
- Money.
- Time.
- Bad luck.
- ...