KB Parallels: SMTP service stops to work with an error like "smtp/tcp server failing (looping), service terminated" in /var/log/messages.

Cause

Such error may occur if there are too many connections to SMTP service occurred.

Resolution

Try to increase maximum connections number. For example on inetd OSes (Debian or FreeBSD) edit /etc/inetd.conf and set:

Debian:

smtp stream tcp nowait.1000 root /var/qmail/bin/tcp-env tcp-env /var/qmail/bin/relaylock /var/qmail/bin/qmail-smtpd /var/qmail/bin/smtp_auth /var/qmail/bin/true /var/qmail/bin/cmd5checkpw /var/qmail/bin/true

smtps stream tcp nowait.1000 root /var/qmail/bin/tcp-env tcp-env /var/qmail/bin/relaylock /var/qmail/bin/qmail-smtpd /var/qmail/bin/smtp_auth /var/qmail/bin/true /var/qmail/bin/cmd5checkpw /var/qmail/bin/true

FreeBSD:

smtp stream tcp nowait/1000 root /usr/local/psa/qmail/bin/tcp-env tcp-env /usr/local/psa/qmail/bin/relaylock /usr/local/psa/qmail/bin/qmail-smtpd /usr/local/psa/qmail/bin/smtp_auth /usr/local/psa/qmail/bin/true /usr/local/psa/qmail/bin/cmd5checkpw /usr/local/psa/qmail/bin/true

smtps stream tcp nowait/1000 root /usr/local/psa/qmail/bin/tcp-env tcp-env /usr/local/psa/qmail/bin/relaylock /usr/local/psa/qmail/bin/qmail-smtpd /usr/local/psa/qmail/bin/smtp_auth /usr/local/psa/qmail/bin/true /usr/local/psa/qmail/bin/cmd5checkpw /usr/local/psa/qmail/bin/true

Also increase number of connections per minute for inetd /etc/rc.conf file, for example:

inetd_flags="-wW -R 5000"

And on RedHat based OSes edit /etc/xinetd.conf:

instances = 200

Then restart inetd/xinetd.

Keywords: debian smtp problem looping stop terminated inetd freebsd

Parallels

SMTP service stops to work with an error like "smtp/tcp server failing (looping), service terminated" in /var/log/messages.

Cause

Resolution

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