- dovecot - dovecot.org

Repeated Inbox Corruption, how to Troubleshoot?
by Bryan K. Walton 21 Dec '20

21 Dec '20

We are running Dovecot Version 2.3.8 (9df20d2db) (from the CentOS 8 repos). Twice in the last week, I've encountered an issue where my Mutt imap client logs into our imap server and has 0 new messages (when I know that there are a lot of new messages waiting on me). Both times, I've had to shut down my mail client, and then run: doveadm -Dv force-resync -u <username> INBOX After which, I reopen Mutt and all of my new emails appear in the inbox of my mail client. Running the force-resync shows no problems. Furthermore, "doveadm log errors" shows no errors on my account and there is nothing in the logs showing that anything is corrupted for me. Yet, the force-resync is fixing a problem that I can't locate. Where should I be looking (or how should I update my logging) so that I can find out the source of the problem that is causing my repeated inbox problems? Thanks! Bryan Walton -- Bryan K. Walton 319-337-3877 Linux Systems Administrator Leepfrog Technologies, Inc

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Fail2ban and login_trusted_networks
by Javi Legido 21 Dec '20

21 Dec '20

Hi there. First of all many thanks to all the people involved in this project for their time, I really appreciate it. Second my use case: a) Container running Webmail (roundcube) with dovecot-ident plugin enabled <https://github.com/roundcube/roundcubemail/issues/5336#issuecomment-2281310…> . b) Container running Dovecot 2.3.4.1 (docker-mailserver-mysql <https://github.com/Kedu-SCCL/docker-mailserver-mysql>) with fail2ban enabled Since I need to add the private IP address of the webmail to "login_trusted_networks" to "...allow to override their IP addresses and ports" I can keep login to webmail even though if the IP is blocked. Question: there's any way to: a) Allow a certain IP range to override it's IP address and ports (as in "login_trusted_networks") but b) Be blocked, as any other incoming connections, by fail2ban? More context. Once the public IP is banned (8.8.8.8 in this example): ``` 2020-12-21 10:10:31,371 fail2ban.filter [309]: INFO [dovecot] Found 8.8.8.8 - 2020-12-21 10:10:31 2020-12-21 10:10:39,189 fail2ban.filter [309]: INFO [dovecot] Found 8.8.8.8 - 2020-12-21 10:10:39 2020-12-21 10:10:51,222 fail2ban.filter [309]: INFO [dovecot] Found 8.8.8.8 - 2020-12-21 10:10:51 2020-12-21 10:10:52,008 fail2ban.actions [309]: NOTICE [dovecot] Ban 8.8.8.8 ``` I can't reach dovecot by telnet from this public IP: ``` telnet mail.example.com 143 Trying 9.9.9... telnet: Unable to connect to remote host: Connection refused ``` Unless I removed the ban: ``` docker exec mail fail2ban-client set dovecot unbanip 8.8.8.8 ``` Many thanks. Javier

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Using dovecot with RoundCubeMail - where is the information for new mail in (blue coloured) directories?
by Philip Rhoades 21 Dec '20

21 Dec '20

People, Every few years I try to work this problem out - occasionally I would like to re-mark a dir as having new mail so that the dir shows up as blue-coloured in RCM. Every time I Google in vain and then have a go at working it out myself but the only thing I can see is that there is a change in the appropriate dir dovecot.index.log file after having the blue dir clicked on (and the colour of the dir name changes back to black) - so is the information stored somewhere in RCM itself? Thanks, Phil. -- Philip Rhoades PO Box 896 Cowra NSW 2794 Australia E-mail: phil(a)pricom.com.au

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Required key not available
by David Matthews 19 Dec '20

19 Dec '20

hello dovecot -n # 2.3.4.1 (f79e8e7e4): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.4 () # OS: Linux 4.19.0-12-amd64 x86_64 Debian 10.0 what is the meaning / cause of this in mail.err:- ---------------------------------------------------------- dovecot: imap(david)<5004><vCVKAtO2UI1/AAAB>: Error: Mailbox Trash: open() failed with mbox: Required key not available ---------------------------------------------------------- I can telnet to port 143, log in and list folders, but cannot open them. This seems to have resulted from an experimental install (now purged) of courier-imap (I maintain a webmail program). Before this, dovecot just worked; now this problem remains even after a reinstall. -- David Matthews mail(a)dmatthews.org

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Using dovecot with RoundCubeMail - where is the information for new mail in (blue coloured) directories?
by Philip Rhoades 19 Dec '20

19 Dec '20

People, Every few years I try to work this problem out - occasionally I would like to re-mark a dir as having new mail so that the dir shows up as blue-coloured in RCM. Every time I Google in vain and then have a go at working it out myself but the only thing I can see is that there is a change in the appropriate dir dovecot.index.log file after having the blue dir clicked on (and the colour of the dir name changes back to black) - so is the information stored somewhere in RCM itself? Thanks, Phil. -- Philip Rhoades PO Box 896 Cowra NSW 2794 Australia E-mail: phil(a)pricom.com.au

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ulimit -n vs client_limit vs process_limit
by Joseph Tam 19 Dec '20

19 Dec '20

As many of my users are accessing their mail remotely, I've seen service loads increase and came across this log messages which I haven't seen before imap-login: Error: socketpair() failed: Too many open files: user=<*>, ... I gather I have to increase file descriptor limits, which is currently set to match default_client_limit = 1000 What should I set "ulimit -n" relative to client_limit? Or perhaps I've roofed service imap-login { process_limit = 2 ... } and should adjust that? Joseph Tam <jtam.home(a)gmail.com>

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Dovecot Replication Errors (only) when using tcps: as the mail_replica Protocol
by Reuben Farrelly 18 Dec '20

18 Dec '20

Hi, I've been seeing errors logged for some time with replication processes, whereby replication sessions seem to be timing out periodically. This is with dovecot version 2.3.10.1 (a3d0e1171) and both are Gentoo x86_64. After some investigation I've determined that these timeouts are only ever occurring with tcps as the replication connection type. These errors never occur if non-encrypted tcp is configured. I've been able to validate this by changing only the replica_type on both ends of the replication configuration to tcp, and with no other changes and after a few days of operation there is not a single error logged. mail_replica = tcps:lightning.reub.net:4813 <<< periodic timeouts mail_replica = tcp:lightning.reub.net:4814 <<< works perfectly Example of the error: Jun 12 15:45:44 thunderstorm.reub.net dovecot[21149]: dsync-local(kaylene)<zx+WKTAU416UMwAAzkCIew>: Error: dsync(lightning.reub.net): I/O has stalled, no activity for 600 seconds (last sent=mailbox_delete, last recv=handshake) Jun 12 15:45:44 thunderstorm.reub.net dovecot[21149]: dsync-local(kaylene)<zx+WKTAU416UMwAAzkCIew>: Error: Timeout during state=recv_mailbox_tree doveadm: Error: Timeout during state=slave_recv_mailbox: 6 Time(s) doveadm: Error: Timeout during state=sync_mails (send=mail_requests recv=attributes): 31 Time(s) doveadm: Error: dsync(thunderstorm.reub.net): I/O has stalled, no activity for 600 seconds (last sent=mail_change (EOL), last recv=mailbox): 31 Time(s) doveadm: Error: dsync(thunderstorm.reub.net): I/O has stalled, no activity for 600 seconds (last sent=mailbox_delete, last recv=mailbox_delete): 6 Time(s) It is seen on both sides of the replication setup. The replica is offsite but only a few ms of latency away and there is no packet loss. The replication is happening over IPv6, and the local firewall is logging that sessions are always permitted, and only ever finishing due to tcp-fin or tcp-rst-from-client . SSL appears to be correctly configured, and it seems that the replication itself is for the most part working. Clients are able to use imaps just fine so I don't think there's anything much wrong from an SSL perspective else I'd be seeing complete replication failure and/or client devices unable to connect. Can anyone suggest how we can further debug this problem? Thanks, Reuben

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Outlook with Dovecot
by Elise 17 Dec '20

17 Dec '20

dovecot-2.3.11.3_1 Hi group, I have a problem with connecting Outlook 2019 client to my server (BSD 21.2). Running Postfix and Dovecot. [all.log] Dec 12 16:53:41 poseidon dovecot[36185]: imap-login: Disconnected (auth failed, 1 attempts in 2 secs): user=<elise(a)xxxxx.xx>, method=PLAIN, rip=82.x.x.x.x, lip=10.x.x.x, TLS: Connection closed, session=<U62faUa24N5SsH9H> Providing the correct email address and password. Strang thing is that with Thunderbird it all works fine; only Outlook is refused. tx, Elise [dovecot.conf] auth_mechanisms = plain login disable_plaintext_auth = no mail_location = mbox:/usr/home/%u:INBOX=/var/mail/%u mail_privileged_group = mail passdb { driver = pam } protocols = imap service auth { unix_listener auth-client { group = mail mode = 0660 user = postfix } unix_listener auth-master { mode = 0666 } user = root } service imap-login { inet_listener imap { address = 10.x.x.x } inet_listener imaps { address = 10.x.x.x } } #service pop3-login { # inet_listener pop3 { # address = 10.x.x.x # } # inet_listener pop3s { # address = 10.x.x.x # } #} ssl = yes ssl_ca = </usr/local/share/certs/ca-root-nss.crt ssl_cert = </usr/local/etc/dehydrated/certs/xxxx.xxx/fullchain.pem ssl_key = </usr/local/etc/dehydrated/certs/xxxx.xxx/privkey.pem ssl_cipher_list = HIGH:+TLSv1.2:+TLSv1.3 ssl_dh = </usr/local/etc/dovecot/dh.pem userdb { driver = passwd } protocol imap { imap_client_workarounds = "delay-newmail tb-extra-mailbox-sep " } #protocol pop3 { # pop3_client_workarounds = outlook-no-nuls oe-ns-eoh # pop3_uidl_format = %08Xu%08Xv #} protocol lda { postmaster_address = postmaster(a)xxxxx.xxxx sendmail_path = /usr/sbin/sendmail mail_plugins = sieve }

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Special files under dovecot mail box
by hfh＠cndns.com 17 Dec '20

17 Dec '20

Hello, even if all the mails(messages) are deleted from my mail box (such as the sent box), the capacity of the following special files will not change, that is, these files will only increase and easily occupy the disk. Is there any other way besides using doveadm index manually? In addition, will these files be affected if they are deleted? -rw-------. 1 vmail vmail 3912 Dec 1 13:52 dovecot.index -rw-------. 1 vmail vmail 127008 Dec 17 17:21 dovecot.index.cache -rw-------. 1 vmail vmail 18800 Dec 17 17:21 dovecot.index.log -rw-------. 1 vmail vmail 1567 Jun 20 2019 dovecot.index.thread Dovecot version is 2.2.36.

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Disallow acces via imap, but keep lmtp running
by Julian Kippels 17 Dec '20

17 Dec '20

Hi all, what is the best way to temporarily disable access to a mailbox via imap, but keep it possible to deliver to the mailbox via lmtp? I want to migrate some mailboxes around and would like to ensure that the users cannot access their mail while doing so. I would like to keep the users from logging in entirely rather than setting ACLs. Thanks in advance Julian

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