Racker Hacker Words of wisdom from a server administrator

To disable reverse lookups in qmail with Plesk, simply add -Rt0 to the server_args line in /etc/xinetd.d/smtp_psa


service smtp
{
socket_type = stream
protocol = tcp
wait = no
disable = no
user = root
instances = UNLIMITED
server = /var/qmail/bin/tcp-env
server_args = -Rt0 /usr/sbin/rblsmtpd -r sbl-xbl.spamhaus.org /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
}


Once that’s been saved, simply restart xinetd:

# /etc/init.d/xinetd restart

WATCH OUT! This change will be overwritten if you change certain mail settings in Plesk, like MAPS protection.