Hi using dovecot 1.0.10 with pop/imap, using maildir, with 2000+ users mostly using pop but many using imap.
Once in a great while I have problems with dovecot pop timing out. If I telnet to port 110 it just takes forever to come up or it doesn't at all, the samething happens on the imap port although 110 is always worst. At 1st when troubleshooting I was not sure what was causing the situation and when I ran out of options I stopped postfix. When I did this dovecot immediately started working again, that is port 110/143 came up fast and all the user logins were fast again. When I restarted postfix after a minute or so dovecot became slow again. While observing this situation I notice that postfix had most of the connections about 300+ in established state, while dovecot was using around 150 connections. After adjusting some of the parameters on postfix and shutting it down multiple times, suddenly everything worked but this time postfix was reporting over 3000 connections mostly in TIME_WAIT state which is normal for us. My question is what do you guys think is happening here, what is the relationship between dovecot/postfix that would cause this to happen. I'm just looking for some suggestions in case this happens again. # 1.0.10: /usr/local/etc/dovecot.conf protocols: imap pop3 ssl_disable: yes disable_plaintext_auth: no login_dir: /usr/local/var/run/dovecot/login login_executable(default): /usr/local/libexec/dovecot/imap-login login_executable(imap): /usr/local/libexec/dovecot/imap-login login_executable(pop3): /usr/local/libexec/dovecot/pop3-login login_greeting: D-V1 NP09 ready. login_process_size: 384 login_processes_count: 55 login_max_processes_count: 450 mail_location: maildir:/home/%1u/%u/Maildir maildir_copy_with_hardlinks: yes maildir_copy_preserve_filename: yes mail_executable(default): /usr/local/libexec/dovecot/imap mail_executable(imap): /usr/local/libexec/dovecot/imap mail_executable(pop3): /usr/local/libexec/dovecot/pop3 mail_plugin_dir(default): /usr/local/lib/dovecot/imap mail_plugin_dir(imap): /usr/local/lib/dovecot/imap mail_plugin_dir(pop3): /usr/local/lib/dovecot/pop3 pop3_uidl_format(default): pop3_uidl_format(imap): pop3_uidl_format(pop3): %08Xu%08Xv pop3_client_workarounds(default): pop3_client_workarounds(imap): pop3_client_workarounds(pop3): outlook-no-nuls oe-ns-eoh auth default: count: 4 passdb: driver: shadow userdb: driver: passwd