- dovecot - dovecot.org

doveadm stateful backup
by Christian 26 Jan '22

26 Jan '22

Hi all, first: I'm using version 2.3.4.1 I manage some rather large imap mailboxes which I want to backup on a regular basis. Some of them have relatively heavy traffic and one of them is greater than 30GB in size. I studied the docs for doveadm backup (https://wiki2.dovecot.org/Tools/Doveadm/Sync) and even did some code research to better understand the process. The docs state that using stateful synchronization is the most efficient way to synchronize mailboxes, therefore I chose this approach. Highlevel overview: - store a copy of the whole maildir in a separate directory (/var/vmail/backup) - backup to this directory once a minute (trying to make most use of transaction logs) using the last state stored within a file - create a backup once a day using tar (full, differential and incremental ones) blocking the backup process of the before mentioned step I quite often receive notifications that doveadm backup returned an exit code of 2, which should be quite normal. These notifications look like that: dsync(another_address(a)my.domain): Warning: Failed to do incremental sync for mailbox INBOX, retry with a full sync (Modseq 171631 no longer in transaction log (highest=177818, last_common_uid=177308, nextuid=177309)) dsync(another_address(a)my.domain): Warning: Mailbox changes caused a desync. You may want to run dsync again: Remote lost mailbox GUID e9149d0ae4e02d532505000026ca4352 (maybe it was just deleted?) Synced another_address(a)my.domain successfully but missing some changes. Took 3 seconds. Starting retry 1... The first message seems to point out that the transaction log got rolled and no more contains the messages from the backup dir, right? I thought about setting mail_index_log_rotate_min_age to 1hour to prevent rolling transaction logs too often, but abandoned this thought and increased the backup interval to once a minute. The warnings still appear so maybe my thoughts about transactions logs are wrong. The second message seems less alarming to me. How does doeveadm backup behave in such situations? Does it directly fall back to a less efficient way of syncing mails? Does the state store the information "retry with a full sync" and the next run uses this mode? To investigate on this I simply measured runtimes an saw that the second/retry run takes a bit longer (up to about 15 seconds) to sync the dir. I'm afraid of losing messages using my approach. Is it safe to always use doveadm backup -s $state? Simply counting one maildirs files within the live directory and the backup copy shows a 100 fewer files within the backup dir although the script runs only since a few days. For reference, see my backup script below. Regards Christian #!/bin/bash # * * * * * /root/bin/backup.sh --sync-only # 12 2 1-7 * * test $(date +\%u) -eq 6 && /root/bin/backup.sh --full # 12 2 8-31 * * test $(date +\%u) -eq 6 && /root/bin/backup.sh --differential # 12 2 * * * test $(date +\%u) -ne 6 && /root/bin/backup.sh synconly=0 differential=0 fullbackup=0 if [ $# -gt 0 ] ; then if [ "$1" == "--sync-only" ] ; then synconly=1 elif [ "$1" == "--differential" ] ; then differential=1 elif [ "$1" == "--full" ] ; then fullbackup=1 fi fi basedir="/var/vmail/backup" targetdir="/var/vmail/backup/done" mailaddresses="one_address(a)my.domain another_address(a)my.domain yet_another(a)my.domain" if [ ! -d "$basedir" ] ; then mkdir -p "$basedir" chown vmail:vmail "$basedir" fi if [ ! -d "$targetdir" ] ; then mkdir -p "$targetdir" chown vmail:vmail "$targetdir" fi for mailaddr in ${mailaddresses} ; do #echo "Creating backup for $mailaddr." domainpart=${mailaddr#*@} localpart=${mailaddr%%@*} lockfile="$basedir/$mailaddr.lock" statefile="$basedir/$mailaddr.state" backupdir="$domainpart/$localpart/Maildir" snapshotfile_full="$basedir/$mailaddr.full.snar" snapshotfile="$basedir/$mailaddr.snar" backup_basename="$basedir/${mailaddr}_$(date '+%Y%m%d_%H%M%S')" ( if [ $synconly -eq 1 ] ; then flock -xn 200 if [ $? -eq 1 ] ; then # failed to acquire lock. Skip mailbox silently. exit fi fi # try to acquire exclusive lock for one minute flock -xw 60 200 if [ $? -eq 1 ] ; then echo "Failed to acquire write lock within 60 seconds. Skipping $mailaddr." exit fi retries=0 retval=1 until [ $retval -eq 0 ] || [ $retries -ge 3 ] ; do let 'retries++' if [ -f "$statefile" ] ; then oldstate=$(head -1 "$statefile") else oldstate="" fi start_time=$(date +%s) ERROR=$((doveadm backup -u "$mailaddr" -s "$oldstate" "maildir:$basedir/$backupdir") 2>&1 > "$statefile") retval=$? end_time=$(date +%s) let 'duration=end_time-start_time' if [ $retval -eq 2 ] ; then #if [ $retries -gt 1 ] ; then echo "$ERROR" echo "Synced $mailaddr successfully but missing some changes. Took $duration seconds. Starting retry $retries..." #fi elif [ $retval -ne 0 ] ; then echo "$ERROR" echo "Syncing $mailaddr failed. Return code $retval. Took $duration seconds. Removing backup directory and starting retry $retries..." rm -rf "$basedir/$backupdir" rm -f "$statefile" "$snapshotfile" elif [ $retries -gt 1 ] ; then echo "Successful sync took $duration seconds." fi done # downgrade lock to shared lock flock -sn 200 [ $synconly -eq 1 ] && exit if [ $retval -ne 0 ] ; then echo "Too many retries. Aborting backup of $mailaddr." exit fi cd "$basedir" if [ $fullbackup -eq 1 ] || [ ! -f "$snapshotfile_full" ] ; then tar -cpzf "${backup_basename}_full.tar.gz" --level=0 -g "$snapshotfile_full" "$backupdir" cp -f "$snapshotfile_full" "$snapshotfile" else suffix="" if [ $differential -eq 1 ] ; then cp -f "$snapshotfile_full" "$snapshotfile" suffix="_diff" fi tar -cpzf "${backup_basename}${suffix}.tar.gz" -g "$snapshotfile" "$backupdir" fi cd - > /dev/null mv "${basedir}/"*.tar.gz "$targetdir" ) 200>"$lockfile" [ $synconly -eq 1 ] && continue # housekeeping newest_full=$(ls -1 "${targetdir}/${mailaddr}_"*_full.tar.gz 2>/dev/null | sort | tail -1) if [ -n "$newest_full" ] ; then #echo "Cleaning up files older than $newest_full..." find "$targetdir" -depth -maxdepth 1 -name "${mailaddr}_*" ! -newer "$newest_full" ! -samefile "$newest_full" -printf 'Deleting %p...\n' -delete fi done

1 1

pop3-login logging double Disconencted
by Noel Butler 26 Jan '22

26 Jan '22

Hi all, Wondering if anyone else is seeing this double Disconnected in the logs with current stable version, it only happens for pop3-login, and only with Too many commands... other pop3-login logging with Disconnected like Connection closed (no auth attempts... etc are fine Example of anomaly - pop3-login: Info: Disconnected: Disconnected: Too many bad commands (no auth attempts in ... If anyone running 2.3.17.1 sees this or does not see it on Too many bad... or at all, kindly mind letting me know, not sure if something has gone haywire here or its a bug that needs reporting since logs indicate this only occurred after updating to the point 1 release. -- Regards, Noel Butler This Email, including attachments, may contain legally privileged information, therefore at all times remains confidential and subject to copyright protected under international law. You may not disseminate this message without the authors express written authority to do so. If you are not the intended recipient, please notify the sender then delete all copies of this message including attachments immediately. Confidentiality, copyright, and legal privilege are not waived or lost by reason of the mistaken delivery of this message.

2 1

noob maildir question
by mikfum 25 Jan '22

25 Jan '22

I would like to ask if it is an acceptable practice to manage messages in the maildir as a file (move them from one folder to another) while dovecot is in stop state thinking that it will be rebuild to the next imap user login thanks for your patience:) mik

5 10

Re: noob maildir question
by mikfum 24 Jan '22

24 Jan '22

thanks ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ Il lunedì 24 gennaio 2022 5:15 AM, Ted Hatfield <ted(a)io-tx.com> ha scritto: > I do this all the time on my server. From one user mailbox to another or > > from one maildir folder to another. On my platform I need to make certain > > owner/group of the moved messages is correct for the user I've moved them > > to. Other than that dovecot appears to re-index on the fly. > > Be aware that this is observed information. Others more knowledgeable may > > have concerns that I'm not aware of or just can't see on my system. > > Ted > > On Mon, 24 Jan 2022, mikfum wrote: > > > I would like to ask if it is an acceptable practice to manage messages in the maildir as a file (move them from > > > > one folder to another) while dovecot is in stop state thinking that it will be rebuild to the next imap user login > > > > thanks for your patience:) > > > > mik

1 0

zlib.read errors after upgrade from 2.3.15 to 2.3.17.1
by Arno Schneider 24 Jan '22

24 Jan '22

After upgrading my mailserver from buster to bullseye and dovecot 2.3.15 to 2.3.17.1 I got the following errors: Jan 22 14:22:32 Warning: doveadm(user1)<2953060><49b0NRQF7GFkDy0ALVPUUA>: mdbox /local/mail/user1/storage: rebuilding indexes Jan 22 14:22:39 Error: doveadm(user2)<2953112><awsPGB8F7GGYDy0ALVPUUA>: dsync(2nd.dovecot.server): read(compress(/local/mail/user2/storage/m.4650)) failed: read(/local/mail/user2/storage/m.4650) failed: zlib.read(/local/mail/user2/storage/m.4650): unexpected EOF at 7038367 (last sent=mail, last recv=mail_request (EOL)) I have 2 dovecot servers in a multi-master configuration. The both servers are synced with dsync and the users are routed through a dovecot directors. Any hints where I can continue to investigate / solve this issue? best regards, arno

1 0

Why would dovecot not be answering
by Ruben Safir 23 Jan '22

23 Jan '22

I am really lost as to why dovecot is not authenticating I have smtpd_sasl_type = dovecot in main.cf and # Postfix smtp-auth unix_listener /var/spool/postfix/private/auth { mode = 0666 user = postfix group = postfix } in /etc/dovecot/conf.d/10-master.conf I want it to authenticate on submition only Everything I read says this should do it, but I am up against a wall. I have no debugging information or log at all to confirm what postfix is doing. -- So many immigrant groups have swept through our town that Brooklyn, like Atlantis, reaches mythological proportions in the mind of the world - RI Safir 1998 http://www.mrbrklyn.com DRM is THEFT - We are the STAKEHOLDERS - RI Safir 2002 http://www.nylxs.com - Leadership Development in Free Software http://www2.mrbrklyn.com/resources - Unpublished Archive http://www.coinhangout.com - coins! http://www.brooklyn-living.com Being so tracked is for FARM ANIMALS and extermination camps, but incompatible with living as a free human being. -RI Safir 2013

3 5

S3 integration w Dovecot
by Martin Olsen 21 Jan '22

21 Jan '22

Good morning, day, evening :P As stated on documentation S3-compatible Storages — Dovecot documentation <https://doc.dovecot.org/configuration_manual/mail_location/obox/s3/> only AWS S3 is officially supported. However, we know that Scality has been successfully integrated at some larger corporations. Particularly curious if anyone has integrated with Pure S3 object storage solution, or any other for that matter? Just looking at some different options. - Sincerely, Martin.

4 3

Stop used or not
by mauric＠gmx.ch 21 Jan '22

21 Jan '22

Sieve scripts running fine, but please what would mean the "Stop", if I have multiple Policy that will run true, I need one stop to finish this per section? if header :is ["from","bcc","to"] ["Email-Address-one", "Email-Address-Two", "and so on"] { fileinto ".\Magic-FolderName"; stop; } thanks

3 4

Upgrade only piegenhole to 0.5.17?
by mauric＠gmx.ch 20 Jan '22

20 Jan '22

Please it's possible to update only piegenhole to 0.5.17, on existing Dovecot installation? Downloading dovecot-2.3-pigeonhole-0.5.17.1 Here I found the update-version, its this the possible way? And why I don't found any Informations on any readme, please point me to the right place. installed version, I think this it's the right view? Please on witch place I can check the Sieve installed module? doveconf | head # 2.3.4.1 (f79e8e7e4): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5 () Also found in file pieg-config /* Define to the version of Pigeonhole for Dovecot. */ #define PIGEONHOLE_VERSION "0.5.4" On Debian 10 I have this installed. dovecot-managesieved 1:2.3.4.1-5+deb10u6 amd64 secure POP3/IMAP server - ManageSie dovecot-sieve 1:2.3.4.1-5+deb10u6 amd64 secure POP3/IMAP server - Sieve filters support also checking the folder /usr/include/dovecot/sieve with intention so found any possible version? Thanks for any update

2 2

sockets created for lmtp
by Mike 20 Jan '22

20 Jan '22

Was recently configuring lmtp to listen in the postfix spool for mail. I set the socket as suggested in the documentation, however, when I look at what sockets were created there was an additional one for dovecot. Since I made the change, my expectation would have been just the one that I set up. I doubt it impacts it negatively, but I wanted to understand if I configured things correctly or not. Thanks. Mike

4 6