Thanks for that. It made it a lot easier.
I typed the command, sent the email and got the below result
[root@ServerB ~]# tail -f /usr/local/psa/var/log/maillog | grep
[email protected]
Mar 17 07:48:27 ServerB postfix/qmgr[26305]: 757081C3119: from=<
[email protected]>, size=1570, nrcpt=1...