Hi all:

I'm using Dovecot with Postfix (via LMTP). Because Postfix doesn't de-duplicate recipients, I'm using sieve to drop duplicates, following this recipe: https://serverfault.com/questions/112958/postfix-aliases-and-duplicate-e-mai...

A "sieve_before" script contains:

require ["duplicate"]; if duplicate { discard; stop; }

It works well, except when the recipient is over quota. Dovecot is configured for tempfail in this case: quota_full_tempfail = yes

When a mail arrives for a user who's over quota, Postfix logs this:

AF4481700032: to=<?@?>, relay=?[private/dovecot-lmtp], delay=0.05, delays=0.05/0/0/0, dsn=4.2.2, status=deferred (host ?[private/dovecot-lmtp] said: 452 4.2.2 <?@?> Quota exceeded (mailbox for user is full) (in reply to end of DATA command))

Approximately 10 minutes later, Postfix retries, and log shows:

dovecot: lmtp(?)<1742912><+EYHBXjidmBAmBoAcAY70w>: sieve: msgid=<489132c2-7b77-cd2f-ce60-439f6558ddcf@?>: marked message to be discarded if not explicitly delivered (discard action) postfix/lmtp[1742691]: AF4481700032: to=<?@?>, relay=?[private/dovecot-lmtp], delay=431, delays=431/0/0/0, dsn=2.0.0, status=sent (250 2.0.0 <?@?> +EYHBXjidmBAmBoAcAY70w Saved) postfix/qmgr[421343]: AF4481700032: removed

The message is then nowhere to be found: it's not delivered to mailbox, bounce isn't sent to the sender, mail is not in postfix queue. Apparently it's been discarded.

I'd say that at first LMTP delivery attempt, sieve records message as seen, even though it is eventually rejected (452 over quota). During second attempt sieve "recognizes" the message as seen before and discards it. (This is just my interpretation of what could be happening.)

Is this a bug or have I misconfigured something? My dovecot -n output is below.

Thanks for help,

Aleš Pečnik

dovecot -n

2.3.7.2 (3c910f64b): /etc/dovecot/dovecot.conf

Pigeonhole version 0.5.7.2 ()

OS: Linux 5.4.0-62-generic x86_64 Ubuntu 20.04.1 LTS

auth_mechanisms = plain login auth_username_chars = abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@: auth_username_format = %Ln auth_worker_max_count = 3 default_vsz_limit = 1 G first_valid_gid = 12 first_valid_uid = 8 hostname = something.org last_valid_gid = 12 last_valid_uid = 8 listen = * mail_access_groups = mail mail_location = maildir:/var/dovecot/%u mail_plugins = " quota mailbox_alias mail_log notify acl" mail_privileged_group = mail namespace { location = maildir:/var/dovecot/public:INDEXPVT=/var/dovecot/%n/public prefix = Public. separator = . subscriptions = no type = public } namespace inbox { inbox = yes location = mailbox Drafts { auto = no special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { auto = subscribe special_use = \Sent } mailbox "Sent Messages" { auto = no special_use = \Sent } mailbox Trash { auto = no special_use = \Trash } prefix = } passdb { args = /etc/dovecot/dovecot-sql-master.conf.ext driver = sql master = yes pass = yes } passdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } plugin { acl = vfile mailbox_alias_new = Sent Messages mailbox_alias_new2 = Sent Items mailbox_alias_new3 = Deleted Items mailbox_alias_new4 = Deleted Messages mailbox_alias_old = Sent mailbox_alias_old2 = Sent mailbox_alias_old3 = Trash mailbox_alias_old4 = Trash quota = maildir:User quota quota_rule = *:storage=200M quota_rule2 = Trash:storage=+50M quota_warning = storage=95%% quota-warning 95 %u quota_warning2 = storage=80%% quota-warning 80 %u sieve = file:/var/dovecot/%n/sieve;active=/var/dovecot/%n/sieve/active.sieve sieve_before = /var/lib/dovecot/sieve.d/ sieve_extensions = +notify +imapflags +editheader +duplicate } postmaster_address = postmaster@something.org protocols = " imap lmtp" quota_full_tempfail = yes service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } } service imap-login { inet_listener imap { port = 143 } inet_listener imaps { port = 0 } process_min_avail = 12 service_count = 0 } service imap-postlogin { executable = script-login /etc/dovecot/postlogin.sh user = $default_internal_user } service imap { executable = imap imap-postlogin } service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0600 user = postfix } } service pop3-login { inet_listener pop3 { port = 0 } inet_listener pop3s { port = 0 } } ssl_cert = </etc/ssl/my.crt ssl_client_ca_dir = /etc/ssl/certs ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it userdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } protocol lmtp { mail_plugins = " quota mailbox_alias mail_log notify acl sieve" } protocol lda { mail_plugins = " quota mailbox_alias mail_log notify acl sieve" } protocol imap { mail_max_userip_connections = 30 mail_plugins = " quota mailbox_alias mail_log notify acl imap_quota imap_acl" }