Hi guys!

I'm using dovecot submission server for clients to send emails and relay them to postfix. Everything works fine unless a client tries to send large (40Mbs) messages. No big deal one can say just set "message_size_limit = 314572800" in postfix and it should just work, but no, it does not, client gets "552 5.2.3 Message size exceeds administrative limit.". I've increased verbosity for smtpd process and get this logs for a failed attempt

Sep 12 13:43:21 mx10 postfix/smtpd[73602]: connection established

Sep 12 13:43:21 mx10 postfix/smtpd[73602]: master_notify: status 0 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: name_mask: resource Sep 12 13:43:21 mx10 postfix/smtpd[73602]: name_mask: software Sep 12 13:43:21 mx10 postfix/smtpd[73615]: watchdog_start: 0x563f80b341b0 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_loop: time left 5 for 0x7fdef6cf4700 0x563f80b393d0 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_loop: time left 5 for 0x7fdef6cf4700 0x563f80b1ee10 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_loop: time left 100 for 0x7fdef6d56b20 0x0 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_loop: time left 1000 for 0x7fdef6cf4720 0x563f80b1ee10 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_loop: time left 1000 for 0x7fdef6cf4720 0x563f80b393d0 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_loop: select_delay 0 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_loop: timer 0x7fdef6cf4700 0x563f80b393d0 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: rewrite stream disconnect Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_disable_readwrite: fd 20 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_cancel_timer: 0x7fdef6cf4700 0x563f80b393d0 -1 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_cancel_timer: 0x7fdef6cf4720 0x563f80b393d0 985 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_loop: timer 0x7fdef6cf4700 0x563f80b1ee10 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: proxymap stream disconnect Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_disable_readwrite: fd 10 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_cancel_timer: 0x7fdef6cf4700 0x563f80b1ee10 -1 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_cancel_timer: 0x7fdef6cf4720 0x563f80b1ee10 985 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: watchdog_stop: 0x563f80b341b0 Sep 12 13:43:21 mx10 postfix/smtpd[73615]: watchdog_start: 0x563f80b341b0 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: connect from localhost[127.0.0.1] Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_loop: time left 85 for 0x7fdef6d56b20 0x0 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: match_list_match: localhost: no match Sep 12 13:43:21 mx10 postfix/smtpd[73615]: event_loop: select_delay 85 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: match_list_match: 127.0.0.1: no match Sep 12 13:43:21 mx10 postfix/smtpd[73602]: match_list_match: localhost: no match Sep 12 13:43:21 mx10 postfix/smtpd[73602]: match_list_match: 127.0.0.1: no match Sep 12 13:43:21 mx10 postfix/smtpd[73602]: smtp_stream_setup: maxtime=300 enable_deadline=0 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: match_hostname: smtpd_client_event_limit_exceptions: localhost ~? 127.0.0.0/8 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: match_hostaddr: smtpd_client_event_limit_exceptions: 127.0.0.1 ~? 127.0.0.0/8 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: > localhost[127.0.0.1]: 220 mx10 ESMTP Postfix (Debian/GNU) Sep 12 13:43:21 mx10 postfix/smtpd[73602]: watchdog_pat: 0x5609a03c01b0 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: vstream_fflush_some: fd 10 flush 47 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: vstream_buf_get_ready: fd 10 got 21 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: < localhost[127.0.0.1]: EHLO mx10 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: match_list_match: localhost: no match Sep 12 13:43:21 mx10 postfix/smtpd[73602]: match_list_match: 127.0.0.1: no match Sep 12 13:43:21 mx10 postfix/smtpd[73602]: > localhost[127.0.0.1]: 250-mx10 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: > localhost[127.0.0.1]: 250-PIPELINING Sep 12 13:43:21 mx10 postfix/smtpd[73602]: > localhost[127.0.0.1]: 250-SIZE 314572800 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: > localhost[127.0.0.1]: 250-VRFY Sep 12 13:43:21 mx10 postfix/smtpd[73602]: > localhost[127.0.0.1]: 250-ETRN Sep 12 13:43:21 mx10 postfix/smtpd[73602]: > localhost[127.0.0.1]: 250-ENHANCEDSTATUSCODES Sep 12 13:43:21 mx10 postfix/smtpd[73602]: > localhost[127.0.0.1]: 250-8BITMIME Sep 12 13:43:21 mx10 postfix/smtpd[73602]: > localhost[127.0.0.1]: 250-DSN Sep 12 13:43:21 mx10 postfix/smtpd[73602]: > localhost[127.0.0.1]: 250 CHUNKING Sep 12 13:43:21 mx10 postfix/smtpd[73602]: watchdog_pat: 0x5609a03c01b0 Sep 12 13:43:21 mx10 postfix/smtpd[73602]: vstream_fflush_some: fd 10 flush 138 Sep 12 13:43:22 mx10 postfix/smtpd[73602]: vstream_buf_get_ready: fd 10 got 6 Sep 12 13:43:22 mx10 postfix/smtpd[73602]: < localhost[127.0.0.1]: QUIT Sep 12 13:43:22 mx10 postfix/smtpd[73602]: > localhost[127.0.0.1]: 221 2.0.0 Bye

looks like submission server just quits

if I configure imap client /Thunderbird to connect directly to postfix everything works just fine.

doveconf -n output is attached just in case