Looks like I've erroneously attributed Monit for the error. According to the logs:
Apr 10 18:40:36 feedback postfix/sendmail[29539]: fatal: [email protected](997): No recipient addresses found in message header Apr 10 18:40:36 feedback postfix/postdrop[29540]: warning: stdin: unexpected EOF in data, record type 78 length 40 Apr 10 18:40:36 feedback postfix/postdrop[29540]: fatal: uid=997: malformed input Indeed looking in to the application responsible, a missing recipient was the cause. For completeness, though, master.cf has: # ========================================================================== # service type private unpriv chroot wakeup maxproc command + args # (yes) (yes) (yes) (never) (100) # ========================================================================== smtp inet n - n - - smtpd So I believe 100 connections are accepted by default. Kind regards, Jamie -----Original Message----- From: monit-general [mailto:[email protected]] On Behalf Of Tino Hendricks Sent: 11 April 2019 09:24 To: This is the general mailing list for monit <[email protected]> Subject: Re: Port 25 check cause of "Unable to open a socket to Sendmail" error? I think, this might only be the case if your postfix is configured to accept just one concurrent connection, i.e. master.cf: # service type private unpriv chroot wakeup maxproc command + args # (yes) (yes) (no) (never) (100) # ========================================================================== smtp inet n - n - 1 smtpd What do the postfix Logs say? Cheers! Tino > Am 11.04.2019 um 10:18 schrieb Jamie Burchell <[email protected]>: > > Hi > > Since configuring a check for Sendmail I’ve started seeing an error from > our CodeIgniter PHP application for the first time: > > Exit status code: 75 > Unable to open a socket to Sendmail > > The check is: > > check process sendmail with pidfile /var/spool/postfix/pid/master.pid > start program = "/bin/systemctl postfix start" > stop program = "/bin/systemctl postfix stop" > restart program = "/bin/systemctl postfix restart" > if failed port 25 protocol smtp then restart if 3 restarts within 5 > cycles then unmonitor > > I’m assuming then, that the port is unavailable to other services that > need it if Monit is checking it? > > TIA > Jamie > -- > To unsubscribe: > https://lists.nongnu.org/mailman/listinfo/monit-general -- To unsubscribe: https://lists.nongnu.org/mailman/listinfo/monit-general -- To unsubscribe: https://lists.nongnu.org/mailman/listinfo/monit-general
