Den 08.11.2018 17:52, skrev Robert Kudyba:

This is still happening after a reboot, Fedora 28. Restarting dovecot fixes the problem. Does anyone know if it could be related to this bug report? *https://bugzilla.redhat.com/show_bug.cgi?id=103401#c130 * and suggested work around to add ports to /proc/sys/net/ipv4/ip_local_reserved_ports? Yes. Nov 8 12:21:41 ourdomain dovecot[1386]: Error: service(pop3-login): listen(*, 995) failed: Address already in use Nov 8 12:21:41 ourdomain dovecot[1386]: Error: service(pop3-login): listen(::, 995) failed: Address already in use Nov 8 12:21:41 ourdomain dovecot[1386]: Error: service(imap-login): listen(*, 993) failed: Address already in use Nov 8 12:21:41 ourdomain dovecot[1386]: Error: service(imap-login): listen(::, 993) failed: Address already in use

If you have nfs clients running, they often step on ports in that range.  Alternate work-around is setting sunrpc.min_resvport = 994 in /etc/sysctl.d/99-whatever.conf

Better would be to move away from port-based "security" (not actually secure at all) . Either switch to samba or nfs v4

dovecot --version 2.2.36 (1f10bfa63)

dovecot -n # 2.2.36 (1f10bfa63): /etc/dovecot/dovecot.conf # OS: Linux 4.18.16-200.fc28.x86_64 x86_64 Fedora release 28 (Twenty Eight) # Hostname: ourdomain.com <http://ourdomain.com> auth_debug = yes debug_log_path = /var/log/dovecot-debug.log mail_debug = yes 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 { driver = pam } ssl = required ssl_cert = </etc/letsencrypt/live/ourdomain.com/fullchain.pem <http://ourdomain.com/fullchain.pem> ssl_cipher_list = PROFILE=SYSTEM ssl_key =  # hidden, use -P to show it userdb { driver = passwd } protocol imap { mail_location = mbox:~/mail:INBOX=/var/mail/%u