Sendmail is currently sending out notifications from prdapp01 and prdapp02.
The current headers from prdapp01 as follows -
Return-Path: root@10-166-152-11.cloud.opsource.net Received: from 10-166-152-11.cloud.opsource.net ([207.20.54.3])
by mx.google.com with ESMTPS id o17si732085vct.60.2015.01.15.21.47.39
for <thirumeninathanm@expertus.com>
(version=TLSv1 cipher=RC4-SHA bits=128/128);
The current headers from prdapp02 as follows -
Return-Path: root@10-166-152-19.cloud.opsource.net Received: from 10-166-152-19.cloud.opsource.net ([207.20.45.152])
by mx.google.com with ESMTPS id f13si4781217qaa.86.2015.01.15.21.49.30
for <thirumeninathanm@expertus.com>
(version=TLSv1 cipher=RC4-SHA bits=128/128);
The proposed changes are to do the following -
DNS changes
Add the DNS entry for A host as mail01.learnexa.com - 207.20.45.3
Add the DNS entry for A host as mail02.learnexa.com - 207.20.45.152
Verify Ports and their impact
verify nmap -v 207.20.45.3 to see the ports which are open in prdapp01 and verify the impact.
verify nmap -v 207.20.45.152 to see the ports which are open in prdapp02 and verify the impact.
on prdapp01
yum install sendmail-cf
change the sendmail configuration as follows -
backup sendmail.cf
go to sendmail.mc
add the line below
define(`confDOMAIN_NAME', `mail01.learnexa.com')dnl
(this is not explicitly defined at this time and therefore the system name is being used by default)
m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf
/etc/init.d/sendmail restart
Test by sending an email using mutt and verify that the headers are reflecting the new change.
on prdapp02
yum install sendmail-cf
change the sendmail configuration as follows -
go to sendmail.mc
add the line below
define(`confDOMAIN_NAME', `mail02.learnexa.com')dnl
(this is not explicitly defined at this time and therefore the system name is being used by default)
m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf
/etc/init.d/sendmail restart
Test by sending an email using mutt and verify that the headers are reflecting the new change.
