Stop sendmail delivering to localhost when email domain matches hostname, stop sendmail intercepting emails to info@ and others - CentOS, RHEL, Fedora

sendmail-fix.sh

#!/bin/bash

##
##
## This scipt was inspired by http://serverfault.com/questions/65365/disable-local-delivery-in-sendmail/128450#128450
## It stops webservers sending mail that is addressed to the local hostname to localhost and instead looks remotely for a mail server
##
##

# Install sendmail-cf as this is required to customise the config
yum install -y sendmail-cf

# Add a couple of lines to the end of the sendmail.mc config file
echo "define(\`MAIL_HUB', \``hostname`.')dnl" >> /etc/mail/sendmail.mc
echo "define(\`LOCAL_RELAY', \``hostname`.')dnl" >> /etc/mail/sendmail.mc

# Fixes an issue where certain email addresses are intercepted by the server
sed '/info:/d' /etc/aliases | sed '/sales:/d' | sed '/support:/d' | sed '/marketing:/d' | sed '/news/d' | sed '/games:/d' | sed '/abuse:/d' | sed '/mail:/d' | sed '/fax:/d' > /etc/newaliases && mv /etc/aliases /etc/aliases.old && mv /etc/newaliases /etc/aliases

# Make the config
/etc/mail/make

# Restart the service
service sendmail restart

To stop the servers redirecting valid email addresses like "info@" to "root@" add the following before line 21:

sed '/info:/d' /etc/aliases | sed '/sales:/d' | sed '/support:/d' | sed '/marketing:/d' | sed '/news/d' | sed '/games:/d' | sed '/abuse:/d' | sed '/mail:/d' | sed '/fax:/d' > /etc/newaliases && mv /etc/aliases /etc/aliases.old && mv /etc/newaliases /etc/aliases

thanks @Sixfifty