Yes, there is currently concurrent usage because the Mail spool is NFS Mounted.
Here is the current configuration: dovecot -n # 2.1.15: /etc/dovecot/dovecot.conf # OS: Linux 3.10.54-server-2.mga3 i686 Mageia 3 base_dir = /var/run/dovecot/ disable_plaintext_auth = no lock_method = dotlock login_greeting = SpamZapper Email ready. login_log_format_elements = user=<%u> method=%m rip=%r lip=%l %c mail_debug = yes mail_fsync = always mail_location = maildir:~/Maildir mail_nfs_index = yes mail_nfs_storage = yes mail_privileged_group = mail mbox_lock_timeout = 15 mins mmap_disable = yes passdb { driver = pam } protocols = imap pop3 service anvil { client_limit = 1000 process_limit = 1 } service auth { user = root } service imap-login { chroot = login client_limit = 10 user = dovecot vsz_limit = 256 M } service pop3-login { chroot = login client_limit = 1024 user = dovecot } ssl = no syslog_facility = local2 userdb { driver = passwd } verbose_proctitle = yes protocol pop3 { mail_max_userip_connections = 20 pop3_logout_format = top=%t/%p, retr=%r/%b, del=%d/%m, size=%s pop3_uidl_format = %08Xv%08Xu } protocol lda { postmaster_address = postmas...@example.com } protocol imap { mail_max_userip_connections = 30 } For the time being, I have isolated usage of POP3 connections on a single Servers, however IMAP is especially problematic. From: Aki Tuomi [mailto:aki.tu...@open-xchange.com] Sent: Friday, October 19, 2018 2:51 AM To: Albert Whale <albert.wh...@it-security-inc.com>; dovecot@dovecot.org Subject: Re: Dovecot 2.2.13 error message On 18.10.2018 15.15, Albert Whale wrote: In attempting to reactivate my IMAP communications with my Email Spool (NFS Mounted), I have gotten the following while attempting to download the Emails via POP3. Oct 18 08:00:45 ns4 dovecot: pop3-login: Login: user=<aewhale>, method=PLAIN, rip=74.109.213.194, lip=66.207.133.232 Oct 18 08:02:40 ns4 dovecot: pop3(aewhale): Error: Timeout (180s) while waiting for dotlock for transaction log file /home/aewhale/Maildir/dovecot.index.log Oct 18 08:02:40 ns4 dovecot: pop3(aewhale): Disconnected: Storage error during logout. top=0/0, retr=11511/1566975544, del=11511/11511, size=1566691807 Oct 18 08:02:58 ns4 dovecot: pop3(aewhale): Connection closed top=0/0, retr=0/0, del=0/11520, size=1566929900 This is significantly more information than what I can receive from 2.1.15, but still does not resolve the communications issues. Any help is certainly appreciated. -- Albert E. Whale, CEH CHS CISA CISSP Hi! Seems something is locking the index. Do you have concurrent usage between two or more nodes for same user? Aki