July 2024 - dovecot - dovecot.org

Seeking Guidance on Dovecot Configuration, Security, and Performance Optimization
by Selena Thomas 23 Jul '24

23 Jul '24

Hi everyone, I am setting up Dovecot for the first time and could use some guidance. I have a couple of questions::- -Configuration Basics: What are the essential configuration files I need to focus on for a basic setup: ?? -Security Best Practices: What steps should I take to ensure my Dovecot server is secure, especially regarding -authentication and SSL/TLS: ?? -Performance Tuning: Are there any tips for optimizing performance for a small to medium-sized deployment: ?? I appreciate any advice or resources you can point me towards. Thanks in advance for your help! With Regards, Selena [flutter/https://www.igmguru.com/digital-marketing-programming/flutter-train…]

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Seeking Guidance on Dovecot Configuration, Security, and Performance Optimization
by Selena Thomas 23 Jul '24

23 Jul '24

Hi everyone, I am setting up Dovecot for the first time and could use some guidance. I have a couple of questions::- -Configuration Basics: What are the essential configuration files I need to focus on for a basic setup: ?? -Security Best Practices: What steps should I take to ensure my Dovecot server is secure, especially regarding -authentication and SSL/TLS: ?? -Performance Tuning: Are there any tips for optimizing performance for a small to medium-sized deployment: ?? I appreciate any advice or resources you can point me towards. Thanks in advance for your help! With Regards, Selena https://www.igmguru.com/digital-marketing-programming/flutter-training/

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Seeking Guidance on Dovecot Configuration, Security, and Performance Optimization
by Selena Thomas 23 Jul '24

23 Jul '24

Hi everyone, I am setting up Dovecot for the first time and could use some guidance. I have a couple of questions::- -Configuration Basics: What are the essential configuration files I need to focus on for a basic setup: ?? -Security Best Practices: What steps should I take to ensure my Dovecot server is secure, especially regarding -authentication and SSL/TLS: ?? -Performance Tuning: Are there any tips for optimizing performance for a small to medium-sized deployment: ?? I appreciate any advice or resources you can point me towards. Thanks in advance for your help! With Regards, Selena [https://www.igmguru.com/digital-marketing-programming/flutter-training/flut…]

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auth-worker doesn't systematically log the IP
by Yassine Chaouche 23 Jul '24

23 Jul '24

Dear list, look at this grep auth-worker | nl output from my dovecot log : 166 Jul 22 15:49:47 auth-worker(24409): Info: sql(hakim.boukhadra(a)domain.tld): unknown user 167 Jul 22 15:49:47 auth-worker(13026): Info: sql(prtg(a)domain.tld): unknown user 168 Jul 22 15:53:00 auth-worker(13026): Info: sql(feriel.abbas(a)domain.tld,10.10.10.19): Password mismatch 169 Jul 22 15:53:15 auth-worker(13026): Info: sql(feriel.abbas(a)domain.tld,10.10.10.19): Password mismatch 170 Jul 22 15:55:26 auth-worker(13026): Info: sql(it_sys(a)domain.tld): unknown user 171 Jul 22 15:59:30 auth-worker(13026): Info: sql(radioaintemouchent.domain.tld,10.10.10.19): unknown user 172 Jul 22 15:59:43 auth-worker(13026): Info: sql(mouadoussama(a)radioalgerie.dz): unknown user 173 Jul 22 16:00:38 auth-worker(13026): Info: sql(it_mam(a)domain.tld): unknown user 174 Jul 22 16:00:58 auth-worker(13026): Info: sql(it_mam(a)domain.tld): unknown user 175 Jul 22 16:02:01 auth-worker(13026): Info: sql(it_mam(a)domain.tld): unknown user 176 Jul 22 16:09:35 auth-worker(13026): Info: sql(it_mam(a)domain.tld): unknown user 177 Jul 22 16:09:42 auth-worker(13026): Info: sql(prtg(a)domain.tld): unknown user 178 Jul 22 16:10:11 auth-worker(13026): Info: sql(it_mam(a)domain.tld): unknown user 179 Jul 22 16:15:37 auth-worker(13026): Info: sql(it_sys(a)domain.tld): unknown user 180 Jul 22 16:26:55 auth-worker(13026): Info: sql(it_mam(a)domain.tld): unknown user 181 Jul 22 16:32:01 auth-worker(13026): Info: sql(it_mam(a)domain.tld): unknown user 182 Jul 22 16:35:37 auth-worker(19555): Info: sql(it_sys(a)domain.tld): unknown user As you can see, sometimes the IP addresses of the dubious login attempts are noted, other times this crucial piece of evidence is conspicuously absent. I am wondering what is the source of all those login attempts? or could those be mere username lookups instead to test for mail deliverability? Many thanks, -- yassine -- sysadm +213-779 06 06 23 http://about.me/ychaouche Looking for side gigs.

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Missing IMAP METADATA Plugin
by Adam Miller 20 Jul '24

20 Jul '24

OS: Ubuntu 22.04.1 Dovecot: 2.3.16 (7e2e900c1a) When trying to enable the “imap_metadata” plugin, I get the following error: Plugin 'imap_metadata' not found from directory /usr/lib/dovecot/modules I have searched high and low via Google, StackOverflow and even ChatGPT (haha) but I cannot seem to find the package that provides the plugin. Does Dovecot have to be built from source for this plugin to be included? Any help is appreciated. Thank you!

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doveadm: SSL handshake failed - wrong version number
by Rachel Roch 19 Jul '24

19 Jul '24

When attempting a doveadm backup, e.g. : doveadm -D backup -Ru user tcp:foo.example.com:12345 I am getting the following error : Error: SSL handshake failed: SSL_accept() failed: error:0A00010B:SSL routines::wrong version number There is nothing wrong with my SSL config because, e.g. openssl s_client -connect localhost:993 works on the source host. So I don't know why doveadm doesn't work. My SSL config is: ssl = required ssl_cert = </etc/ssl/foo.example.com.pem ssl_key = </etc/ssl/foo.example.com.priv ssl_client_ca_dir = /etc/ssl/certs ssl_min_protocol = TLSv1.2 ssl_prefer_server_ciphers = yes ssl_cipher_list = ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-CHACHA20-POLY1305 service doveadm { inet_listener { port = 12345 ssl = yes } }

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dovecot.list.index.log
by Joan Moreau 19 Jul '24

19 Jul '24

HI Is it safe to delete the file dovecot.list.index.log (as I am still struggling with using any protocol for network storage of the emails (dbox), and now dovecot complains that my dovecot.list.index.log is corrupted) Thank you

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AD authentication with dovecot not working.
by hkhk_exact10 19 Jul '24

19 Jul '24

Hi All, I am trying to setup AD auth with dovecot and have tried a lot of options but still no success. I am using a bind account for AD authentication and the users are not posix accounts. I am not using the ssl cert as its not available, so disabling it. I have used the similar settings with saslauthd+postfix and it worked, not sure what am I doing wrong with configurations.. My configuration is as follows: # dovecot --version 2.3.16 (7e2e900c1a) # dovecot -n # 2.3.16 (7e2e900c1a): /etc/dovecot/dovecot.conf # OS: Linux 5.14.0-474.el9.x86_64 x86_64 CentOS Stream release 9 # Hostname: mail-centos.example.com auth_mechanisms = plain login first_valid_uid = 1000 listen = * mail_location = maildir:~/Maildir mbox_write_locks = fcntl 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 { args = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap } service auth { unix_listener /var/spool/postfix/private/auth { mode = 0666 } } service pop3-login { process_limit = 500 } service submission-login { inet_listener submission { port = 587 } } ssl_cert = </etc/ssl/example.com/server.pem ssl_cipher_list = PROFILE=SYSTEM ssl_key = # hidden, use -P to show it userdb { args = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap } ------------------ # cat /etc/dovecot/dovecot-ldap.conf.ext uris = ldaps://10.1.85.11 dn = CN=s_linux_bind,OU=Global,OU=Services,OU=Accounts,OU=root,DC=example,DC=com dnpass = xxxxx auth_bind = yes tls_require_cert = never debug_level = 1 ldap_version = 3 base = dc=example,dc=com scope = subtree deref = never user_filter = (&(objectClass=user)(sAMAccountName=%u)) --------------- Error logs: dovecot[6600]: auth: Error: ** ld 0x556695138d90 Outstanding Requests: dovecot[6600]: auth: Error: * msgid 2, origid 2, status RequestCompleted dovecot[6600]: auth: Error: outstanding referrals 2, parent count 2 dovecot[6600]: auth: Error: * msgid 3, origid 2, status InProgress dovecot[6600]: auth: Error: outstanding referrals 0, parent count 2 dovecot[6600]: auth: Error: * msgid 5, origid 2, status InProgress dovecot[6600]: auth: Error: outstanding referrals 0, parent count 1 dovecot[6600]: auth: Error: ld 0x556695138d90 request count 3 (abandoned 0) dovecot[6600]: auth: Error: ** ld 0x556695138d90 Response Queue: dovecot[6600]: auth: Error: Empty dovecot[6600]: auth: Error: ld 0x556695138d90 response count 0 dovecot[6600]: auth: Error: ldap_chkResponseList ld 0x556695138d90 msgid -1 all 0 dovecot[6600]: auth: Error: ldap_chkResponseList returns ld 0x556695138d90 NULL dovecot[6600]: auth: Error: ldap_int_select postfix/submission/smtpd[6602]: warning: unknown[10.1.70.75]: SASL LOGIN authentication failed: Connection lost to authentication server postfix/submission/smtpd[6602]: disconnect from unknown[10.1.70.75] ehlo=2 starttls=1 auth=0/1 quit=1 commands=4/5 Attaching the detailed error logs. --------- saslauthd settings which worked: # cat /etc/saslauthd.conf ldap_servers: ldaps://10.1.85.11 ldap_search_base: dc=wtg,dc=zone ldap_filter: (sAMAccountName=%u) ldap_bind_dn: CN=s_linux_bind,OU=Global,OU=Services,OU=Accounts,OU=root,DC=example,DC=com ldap_password: xxxx ldap_tls_reqcert: never Regards, Sandeep

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Invalid/Unmapped Key with Last Login Plugin
by Adam Miller 18 Jul '24

18 Jul '24

OS: Ubuntu 22.04.1 Dovecot: 2.3.16 (7e2e900c1a) Hello all! I have the last login plugin working with the IMAP service however with LMTP, it errors. I do not necessarily need / want the LMTP service and did not explicitly enable it but it is throwing an error in my logs. Jul 17 10:22:14 lmtp(184051):Error: last_login_dict: Failed to write value: dict-server returned failure: sql dict set: Invalid/unmapped key:shared/last-login/lmtp/username@domain.com/ (reply took 0.234 secs (0.001 in dict wait, 0.033 in other ioloops, 0.030 in locks, as ync-id reply 0.000 secs ago, started on dict-server 0.220 secs ago, took 0.000 secs)) It would be nice to get rid of this error one or another: either disable last login for LMTP or get it working. Current Configuration from doveconf -n # 2.3.16 (7e2e900c1a): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.16 (09c29328) # OS: Linux 6.5.0-1020-aws x86_64 Ubuntu 22.04.4 LTS nfs4 # Hostname: ec2-us-east-1a-arda-mail-001.ardaemail.com auth_mechanisms = plain login auth_worker_max_count = 5 base_dir = /var/run/dovecot debug_log_path = /var/log/dovecot/debug.log default_internal_group = ardaemail default_internal_user = ardaemail dict { quota = mysql:/etc/dovecot/inc.d/inc.quota.user.sql.conf sql = mysql:/etc/dovecot/inc.d/inc.lastlogin.sql.conf } hostname = = mail.ardaemail.com info_log_path = /var/log/dovecot/info.log instance_name = ec2-us-east-1a-arda-mail-001.ardaemail.com listen = 172.16.0.200 log_path = /var/log/dovecot/general.log login_greeting = Welcome to ArdaEmail mail_gid = ardaemail mail_location = maildir:/mnt/mail/%d/%n mail_max_userip_connections = 1000 mail_plugins = " quota mailbox_alias last_login" mail_server_admin = mailto:support@ardaemail.com mail_uid = ardaemail maildir_stat_dirs = yes namespace inbox { inbox = yes location = mailbox Archive { auto = subscribe special_use = \Archive } mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Junk { auto = subscribe autoexpunge = 90 days special_use = \Junk } mailbox Sent { auto = subscribe special_use = \Sent } mailbox Trash { auto = subscribe autoexpunge = 30 days special_use = \Trash } prefix = } passdb { args = /etc/dovecot/inc.d/inc.sql.conf driver = sql } plugin { imapsieve_mailbox1_before = file:/etc/dovecot/sieve.d/spam/learn-spam.sieve imapsieve_mailbox1_causes = COPY imapsieve_mailbox1_name = Junk imapsieve_mailbox2_before = file:/etc/dovecot/sieve.d/spam/learn-ham.sieve imapsieve_mailbox2_causes = COPY imapsieve_mailbox2_from = Junk imapsieve_mailbox2_name = * last_login_dict = proxy::sql last_login_key = # hidden, use -P to show it last_login_precision = ms mailbox_alias_new = Junk Email mailbox_alias_new2 = Junk E-mail mailbox_alias_new3 = Sent Messages mailbox_alias_new4 = Sent Items mailbox_alias_new5 = Deleted Items mailbox_alias_new6 = Junk Mail mailbox_alias_old = Junk mailbox_alias_old2 = Junk mailbox_alias_old3 = Sent mailbox_alias_old4 = Sent mailbox_alias_old5 = Trash mailbox_alias_old6 = Junk quota = dict:User Quota::proxy::quota quota_exceeded_message = Mailbox is full and cannot receive any more emails quota_status_nouser = DUNNO quota_status_success = DUNNO quota_warning = bytes=95%% quota-warning 95 %u quota_warning2 = bytes=85%% quota-warning 85 %u quota_warning3 = bytes=75%% quota-warning 75 %u recipient_delimiter = + sieve_after = /etc/dovecot/sieve.d/after/ sieve_before = /etc/dovecot/sieve.d/before/ sieve_extensions = +spamtest +spamtestplus +virustest +notify +imapflags sieve_global_extensions = +vnd.dovecot.pipe sieve_pipe_bin_dir = /etc/dovecot/sieve sieve_plugins = sieve_imapsieve sieve_extprograms sieve_quota_max_storage = 0 sieve_spamtest_max_header = X-Spamd-Result: -?[[:digit:]]+\.[[:digit:]]+ / (-?[[:digit:]]+\.[[:digit:]]) sieve_spamtest_status_header = X-Spamd-Result: (-?[[:digit:]]+\.[[:digit:]]+) / -?[[:digit:]]+\.[[:digit:]] sieve_spamtest_status_type = score } postmaster_address = postmaster(a)ardaemail.com protocols = imap lmtp service auth-worker { group = ardaemail user = ardaemail } service auth { group = ardaemail unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } unix_listener auth-userdb { group = ardaemail mode = 0666 user = ardaemail } user = ardaemail } service imap-login { inet_listener imap { port = 0 } inet_listener imaps { port = 993 ssl = yes } process_min_avail = 8 service_count = 0 } service imap { vsz_limit = 4 G } service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0666 user = postfix } } service pop3-login { inet_listener pop3 { port = 0 } inet_listener pop3s { port = 0 } } service quota-status { executable = /usr/lib/dovecot/quota-status -p postfix unix_listener /var/spool/postfix/private/quota-status { user = postfix } } service quota-warning { executable = script /etc/dovecot/bin/quota-warning.sh unix_listener quota-warning { group = ardaemail mode = 0666 user = ardaemail } } service submission-login { inet_listener submission { port = 0 } } ssl = required ssl_cert = </etc/letsencrypt/live/mail.ardaemail.com/fullchain.pem ssl_client_ca_dir = /etc/ssl/certs ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it ssl_prefer_server_ciphers = yes userdb { args = /etc/dovecot/inc.d/inc.sql.conf driver = sql } protocol imap { mail_plugins = " quota mailbox_alias last_login imap_sieve imap_quota last_login" } protocol lmtp { mail_plugins = " quota mailbox_alias last_login sieve" } In the configuration above, I do not have "last_login" in my actual config for "protocol lmtp", something is adding it. Any help is appreciated. Thank you!

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Missing IMAP METADATA Plugin
by Adam Miller 18 Jul '24

18 Jul '24

OS: Ubuntu 22.04.1 Dovecot: 2.3.16 (7e2e900c1a) When trying to enable the “imap_metadata” plugin, I get the following error: Plugin 'imap_metadata' not found from directory /usr/lib/dovecot/modules I have searched high and low via Google, StackOverflow and even ChatGPT (haha) but I cannot seem to find the package that provides the plugin. Does Dovecot have to be built from source for this plugin to be included? Current Configuration from doveconf -n # 2.3.16 (7e2e900c1a): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.16 (09c29328) # OS: Linux 6.5.0-1020-aws x86_64 Ubuntu 22.04.4 LTS nfs4 # Hostname: ec2-us-east-1a-arda-mail-001.ardaemail.com auth_mechanisms = plain login auth_worker_max_count = 5 base_dir = /var/run/dovecot debug_log_path = /var/log/dovecot/debug.log default_internal_group = ardaemail default_internal_user = ardaemail dict { quota = mysql:/etc/dovecot/inc.d/inc.quota.user.sql.conf sql = mysql:/etc/dovecot/inc.d/inc.lastlogin.sql.conf } hostname = = mail.ardaemail.com info_log_path = /var/log/dovecot/info.log instance_name = ec2-us-east-1a-arda-mail-001.ardaemail.com listen = 172.16.0.200 log_path = /var/log/dovecot/general.log login_greeting = Welcome to ArdaEmail mail_gid = ardaemail mail_location = maildir:/mnt/mail/%d/%n mail_max_userip_connections = 1000 mail_plugins = " quota mailbox_alias last_login" mail_server_admin = mailto:support@ardaemail.com mail_uid = ardaemail maildir_stat_dirs = yes namespace inbox { inbox = yes location = mailbox Archive { auto = subscribe special_use = \Archive } mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Junk { auto = subscribe autoexpunge = 90 days special_use = \Junk } mailbox Sent { auto = subscribe special_use = \Sent } mailbox Trash { auto = subscribe autoexpunge = 30 days special_use = \Trash } prefix = } passdb { args = /etc/dovecot/inc.d/inc.sql.conf driver = sql } plugin { imapsieve_mailbox1_before = file:/etc/dovecot/sieve.d/spam/learn-spam.sieve imapsieve_mailbox1_causes = COPY imapsieve_mailbox1_name = Junk imapsieve_mailbox2_before = file:/etc/dovecot/sieve.d/spam/learn-ham.sieve imapsieve_mailbox2_causes = COPY imapsieve_mailbox2_from = Junk imapsieve_mailbox2_name = * last_login_dict = proxy::sql last_login_key = # hidden, use -P to show it last_login_precision = ms mailbox_alias_new = Junk Email mailbox_alias_new2 = Junk E-mail mailbox_alias_new3 = Sent Messages mailbox_alias_new4 = Sent Items mailbox_alias_new5 = Deleted Items mailbox_alias_new6 = Junk Mail mailbox_alias_old = Junk mailbox_alias_old2 = Junk mailbox_alias_old3 = Sent mailbox_alias_old4 = Sent mailbox_alias_old5 = Trash mailbox_alias_old6 = Junk quota = dict:User Quota::proxy::quota quota_exceeded_message = Mailbox is full and cannot receive any more emails quota_status_nouser = DUNNO quota_status_success = DUNNO quota_warning = bytes=95%% quota-warning 95 %u quota_warning2 = bytes=85%% quota-warning 85 %u quota_warning3 = bytes=75%% quota-warning 75 %u recipient_delimiter = + sieve_after = /etc/dovecot/sieve.d/after/ sieve_before = /etc/dovecot/sieve.d/before/ sieve_extensions = +spamtest +spamtestplus +virustest +notify +imapflags sieve_global_extensions = +vnd.dovecot.pipe sieve_pipe_bin_dir = /etc/dovecot/sieve sieve_plugins = sieve_imapsieve sieve_extprograms sieve_quota_max_storage = 0 sieve_spamtest_max_header = X-Spamd-Result: -?[[:digit:]]+\.[[:digit:]]+ / (-?[[:digit:]]+\.[[:digit:]]) sieve_spamtest_status_header = X-Spamd-Result: (-?[[:digit:]]+\.[[:digit:]]+) / -?[[:digit:]]+\.[[:digit:]] sieve_spamtest_status_type = score } postmaster_address = postmaster(a)ardaemail.com protocols = imap lmtp service auth-worker { group = ardaemail user = ardaemail } service auth { group = ardaemail unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } unix_listener auth-userdb { group = ardaemail mode = 0666 user = ardaemail } user = ardaemail } service imap-login { inet_listener imap { port = 0 } inet_listener imaps { port = 993 ssl = yes } process_min_avail = 8 service_count = 0 } service imap { vsz_limit = 4 G } service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0666 user = postfix } } service pop3-login { inet_listener pop3 { port = 0 } inet_listener pop3s { port = 0 } } service quota-status { executable = /usr/lib/dovecot/quota-status -p postfix unix_listener /var/spool/postfix/private/quota-status { user = postfix } } service quota-warning { executable = script /etc/dovecot/bin/quota-warning.sh unix_listener quota-warning { group = ardaemail mode = 0666 user = ardaemail } } service submission-login { inet_listener submission { port = 0 } } ssl = required ssl_cert = </etc/letsencrypt/live/mail.ardaemail.com/fullchain.pem ssl_client_ca_dir = /etc/ssl/certs ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it ssl_prefer_server_ciphers = yes userdb { args = /etc/dovecot/inc.d/inc.sql.conf driver = sql } protocol imap { mail_plugins = " quota mailbox_alias last_login imap_sieve imap_quota last_login" } protocol lmtp { mail_plugins = " quota mailbox_alias last_login sieve" } Any help is appreciated. Thank you!

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