I'm using dovecot in a multi server setup. Two directors forward pop3, imap and smtp to backend dovecots with their central storage on NFS. Yesterday I stumbled upon these log lines:
2019-11-18 20:17:51 lmtp(17274): Info: Connect from 172.22.1.6 2019-11-18 20:17:51 lmtp(17274): Panic: file smtp-client-connection.c: line 1142 (smtp_client_connection_established): assertion failed: (!conn->connect_succeeded) 2019-11-18 20:17:51 lmtp(17274): Fatal: master: service(lmtp): child 17274 killed with signal 6 (core not dumped - https://dovecot.org/bugreport.html#coredumps - set /proc/sys/fs/suid_dumpable to 2)
Is a core dump required to find the source of that error?
Thanks for any help!
$ doveconf -n # 2.3.4.1 (f79e8e7e4): /etc/dovecot/dovecot.conf # OS: Linux 4.9.0-8-amd64 x86_64 # Hostname: m03.company.com auth_cache_negative_ttl = 65 secs auth_cache_ttl = 3 mins auth_cache_verify_password_with_worker = yes auth_mechanisms = plain login auth_verbose = yes debug_log_path = /dev/stdout default_client_limit = 10400 default_process_limit = 1024 default_vsz_limit = 1 G deliver_log_format = msgid=%m: %s %{session_time} %$ director_mail_servers = 10.10.10.2 10.10.10.3 director_servers = 10.10.1.2 10.10.1.3 imap_id_log = * imap_max_line_length = 2 M import_environment = TZ CORE_OUTOFMEM CORE_ERROR info_log_path = /dev/stdout instance_name = dovecot_director listen = 10.10.1.3,:: lmtp_proxy = yes log_path = /dev/stderr log_timestamp = "%Y-%m-%d %H:%M:%S " login_log_format_elements = user=<%u> method=%m rip=%r lip=%l mpid=%e %c %k session=<%{session}> mail_max_userip_connections = 250 passdb { args = /etc/dovecot/sql/dovecot-dict-sql-passdb.conf driver = sql result_failure = return-fail result_internalfail = return-fail result_success = continue-ok } passdb { args = proxy=y starttls=any-cert master=director@m03.company.com pass=#hidden_use-P_to_show# nopassword=y driver = static skip = unauthenticated } pop3_logout_format = top=%t/%p, retr=%r/%b, del=%d/%m, size=%s, uidl=%u protocols = imap lmtp pop3 service auth-worker { user = $default_internal_user } service director { fifo_listener login/proxy-notify { mode = 0600 user = $default_login_user } inet_listener { port = 9090 } unix_listener director-userdb { mode = 0600 user = vmail } unix_listener login/director { mode = 0666 } } service imap-login { executable = imap-login director process_min_avail = 2 vsz_limit = 1 G } service lmtp { inet_listener lmtp { port = 24 } process_min_avail = 2 unix_listener lmtp { mode = 00 } user = vmail vsz_limit = 1 G } service log { user = dovenull } service pop3-login { executable = pop3-login director process_min_avail = 2 vsz_limit = 1 G } service pop3 { user = vmail } ssl_cert =