November 2021 - dovecot

Strategies for protecting IMAP (e.g. MFA)
by Tyler Montney 02 Dec '21

02 Dec '21

With the world of ransomware as it is today (aka attacks seem more vicious and commonplace), anything I expose to WAN must have additional protection. I've seen a few posts to this list on it. The only thing that helped was that Dovecot supports OAuth. Through OAuth I figure I could implement MFA. However, I'd have to host my own identity server. From there, Thunderbird supports OAuth so that should work. Since this is getting increasingly complicated, I wanted to ask before going further. What do you all do? Any recommendations?

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Strange errors with Dovecot replication
by Claudio Corvino 01 Dec '21

01 Dec '21

Hi, I have two IMAP/LMTP Dovecot server in replica (version 2.3.4.1) for testing purposes, both connected through an IPsec tunnel, I use LDAP/AD for /userdb, /all seems to work fine except for these errors present in logs every day: NODE A: /doveadm: Error: sieve: file storage: utime(/var/www/html/ooo/its-test) failed: Operation not permitted: 28 Time(s) dsync-local(its-test)<TxExKuQgeWHlTAAA045Smw>: Error: read(xxx) failed: Connection reset by peer (last sent=mailbox_delete, last recv=handshake): 1 Time(s) dsync-local(its-test)<fXcyHCd3eWGHXwAA045Smw>: Error: sieve: file storage: utime(/var/www/html/ooo/its-test) failed: Operation not permitted: 2 Time(s) dsync-local(its-test)<fZ2LISh3eWGOXwAA045Smw>: Error: read(xxx) failed: Connection reset by peer (last sent=mailbox_delete, last recv=handshake): 1 Time(s) dsync-local(its-test2)<PqNdGCd3eWGGXwAA045Smw>: Error: read(xxx) failed: Connection reset by peer (last sent=mailbox_delete, last recv=handshake): 1 Time(s)/ NODE B: /doveadm: Error: Couldn't lock /mnt/mail-storage-dev/its-test/.dovecot-sync.lock: fcntl(/mnt/mail-storage-dev/its-test/.dovecot-sync.lock, write-lock, F_SETLKW) locking failed: Timed out after 30 seconds: 2 Time(s) doveadm: Error: Couldn't lock /mnt/mail-storage-dev/its-test2/.dovecot-sync.lock: fcntl(/mnt/mail-storage-dev/its-test2/.dovecot-sync.lock, write-lock, F_SETLKW) locking failed: Timed out after 30 seconds: 1 Time(s) doveadm: Error: sieve: file storage: utime(/var/www/html/ooo/its-test) failed: Operation not permitted: 28 Time(s) dsync-local(its-test)<QtV8HSh3eWHFDgAA/HgeEQ>: Error: sieve: file storage: utime(/var/www/html/ooo/its-test) failed: Operation not permitted: 2 Time(s)/ What I have to do? Do I have to worry about this or I can ignore it? Thanks Regards

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sieve - segmentation fault
by kjonca＠o2.pl 01 Dec '21

01 Dec '21

I tried to experiment with "index" extension and I found that, in case "0" sieve-filter segfaults. example code was: --8<---------------cut here---------------start------------->8--- if header :index 0 :last :regex "received" "some regex here" { fileinto "dedicated mailbox" ; } --8<---------------cut here---------------end--------------->8--- KJ -- http://stopstopnop.pl/stop_stopnop.pl_o_nas.html I dote on his very absence. -- William Shakespeare, "The Merchant of Venice"

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/var/run/dovecot/stats-writer) failed: No such file or directory
by Brent Clark 01 Dec '21

01 Dec '21

Good day Guys I am getting this error message in the logs. dovecot: imap-login: Error: net_connect_unix(/var/run/dovecot/stats-writer) failed: No such file or directory Running Debian Buster. With a bit of googling, I tried the suggestions of: https://forum.iredmail.org/post67042.html#p67042 https://git.ispconfig.org/ispconfig/ispconfig3/-/issues/5343 But still this problem is persisting. Here is the config. ~ # cat /etc/dovecot/conf.d/20-dovecot-stats.conf service stats { unix_listener stats-writer { user = dovecot group = mail mode = 0660 } } ~ # ls -la /var/run/dovecot/stats-writer srw-rw---- 1 dovecot mail 0 Nov 21 17:00 /var/run/dovecot/stats-writer Could anyone please shed an idea or tip of where more too can I look. Many thanks Regards Brent Clark

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Fatal: master: service(imap): child 1288 killed with signal 6
by fugee ohu 01 Dec '21

01 Dec '21

This error appears in mail.log repeatedly after dovecot startup Notice the 777 mode for service auth I set that myself # doveconf -n # 2.3.7.2 (3c910f64b): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.7.2 () # OS: Linux 5.14.17-x86_64-linode150 x86_64 Ubuntu 20.04.3 LTS # Hostname: mail.servicemouse.com auth_verbose = yes mail_privileged_group = mail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = } passdb { driver = pam } plugin { sieve = file:~/sieve;active=~/.dovecot.sieve } protocols = " imap lmtp sieve pop3 submission" service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0777 user = postfix } } ssl_cert = </etc/letsencrypt/live/mail.servicemouse.com/fullchain.pem ssl_client_ca_dir = /etc/letsencrypt/live/mail.servicemouse.com ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it submission_relay_host = 127.0.0.1 submission_relay_ssl = starttls submission_relay_trusted = yes userdb { driver = passwd }

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dovecot Error: Failed to establish relay connection: Failed to connect to remote server
by fugee ohu 27 Nov '21

27 Nov '21

# doveconf -n # 2.3.7.2 (3c910f64b): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.7.2 () # OS: Linux 5.14.17-x86_64-linode150 x86_64 Ubuntu 20.04.3 LTS # Hostname: mail.servicemouse.com auth_verbose = yes mail_privileged_group = mail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = } passdb { driver = pam } plugin { sieve = file:~/sieve;active=~/.dovecot.sieve } protocols = " imap lmtp sieve pop3 submission" service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } } ssl_cert = </etc/letsencrypt/live/mail.servicemouse.com/fullchain.pem ssl_client_ca_dir = /etc/letsencrypt/live/mail.servicemouse.com ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it submission_relay_host = 127.0.0.1 submission_relay_ssl = starttls submission_relay_trusted = yes userdb { driver = passwd }

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Disable sieve redirection
by Lefteris Tsintjelis 27 Nov '21

27 Nov '21

Hi, is there a way to control sieve redirection or even disable it completely?

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Spam Folder
by bobby 26 Nov '21

26 Nov '21

I have been following the tutorial here: https://www.linuxbabe.com/mail-server/block-email-spam-check-header-body-wi… I notice that when I log into my mail via nextcloud mail, there is no spam folder. Is there something further I need to do so it is generated?

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Can't unsubscribe from public mailbox when dsync multi-master is enabled
by Salatiel Filho 25 Nov '21

25 Nov '21

Hello, I am trying to build a dovecot environment with 2 servers with dsync master<->master replication. Everything works just fine, one can login in any of the servers and see and manage their mails. The problem I see is that one can not unsubscribe from public mailboxes. Let's call the servers server1 and server2, both of them have an imap webui pointing to localhost, just to make the test easier. One subscribes to a public mailbox connected through the webui on server1. A few seconds later the same user can see the subscribed mailbox on the webui on server2 just as expected, but if he tries to unsubscribe it will not work. The public mailbox folder will still be subscribed to and visible. There is absolutely nothing on the logs, but I know it is related to the dsync replication because if I shutdown any of the servers, I will be able to unsubscribe just fine, UNTIL the shutdown server is powered back on and replication starts again, and, in this case, the previously unsubscribed public mailbox will just reappear. Is this a bug or am I missing something in my configuration? Thanks! # dovecot -n # 2.3.16 (7e2e900c1a): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.16 (09c29328) # OS: Linux 4.18.0-305.19.1.el8_4.x86_64 x86_64 auth_username_format = %Ln doveadm_password = # hidden, use -P to show it first_valid_uid = 1000 mail_debug = yes mail_home = /var/spool/imap/%n mail_location = maildir:/var/spool/imap/%n/mail:VOLATILEDIR=/var/spool/imap/%n mail_plugins = " notify replication" managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext namespace { list = children location = maildir:/var/spool/imap/salas/mail/:INDEXPVT=/var/spool/imap/%n/pub-seen-idx/ mailbox * { autoexpunge = 60 days } prefix = salas/ separator = / subscriptions = no type = public } namespace inbox { inbox = yes location = mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { auto = subscribe special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { auto = subscribe special_use = \Trash } prefix = separator = / } passdb { args = scheme=CRYPT username_format=%n /etc/dovecot/users driver = passwd-file } passdb { args = failure_show_msg=yes dovecot driver = pam } plugin { mail_replica = tcps:10.10.10.10:26 sieve = file:/var/spool/imap/%n/sieve;active=/var/spool/imap/%n/.dovecot.sieve sieve_before = /var/lib/dovecot/sieve.d/ sieve_global = /var/lib/dovecot/sieve.d/ } protocols = imap lmtp sieve replication_dsync_parameters = -d -N -l 10 -U service aggregator { fifo_listener replication-notify-fifo { mode = 0666 user = dovecot } unix_listener replication-notify { mode = 0666 user = dovecot } } service doveadm { inet_listener { port = 26 ssl = yes } } service replicator { process_min_avail = 1 unix_listener replicator-doveadm { mode = 0666 user = dovecot } } ssl = required ssl_ca = </etc/ssl/certs/mail-cluster-communication_ca.pem ssl_cert = </etc/ssl/certs/mail-cluster-communication.crt ssl_key = # hidden, use -P to show it userdb { args = username_format=%n /etc/dovecot/users default_fields = uid=vmail gid=mail home=/var/spool/imap driver = passwd-file } userdb { driver = passwd override_fields = uid=vmail gid=mail home=/var/spool/imap/%n } protocol lmtp { mail_plugins = " notify replication sieve" } protocol imap { ssl_cert = </etc/ssl/certs/salas.com.crt ssl_key = # hidden, use -P to show it }

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special-use missing in 2.3 imap connection
by Marc 25 Nov '21

25 Nov '21

Should I specify special_use any where, it is missing from my telnet imap.local 143 2.2: * OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE SPECIAL-USE STARTTLS AUTH=PLAIN] Dovecot ready. 2.3: * OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE STARTTLS AUTH=PLAIN] Dovecot ready.

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