One good trick to use when testing your email server is to use telnet. To send email, you can just telnet into the destination email server directly: u-1@srv-1 u-1 $ telnet yourmailserver.com 25 Trying 21.40.23.46… Connected to yourmailserver.com. Escape character is ‘^]’. 220 mx.yourmailserver.com ESMTP Sendmail 8.12.9/8.12.9; Thu, 12 Jun 2003 10:06:19 -0700 helo frommail.com […]
Test SMTP (email) via Telnet
Osirusoft Is Blocking All Hosts
Due to DDoS attacks on Osirusoft, Osirusoft decided to reject all. So, if you are using Osirusoft to block spam, stop! Well, hats off to the valiant efforts of Osirusoft. Can’t really blame them for their reaction to this world of shit. The beautiful thing is that sysadmins and others in our community will find […]
Using Watch-maillog To Reduce Spam Chatter
It is truly amazing how many resources are taken up on a server by other rogue boxes searching for an open relay, or simply sending dictionary attempts at finding local users. Watch-maillog is a perl script that uses IPtables to block mail servers that abuse your server. Watch-maillog helps with this by blocking servers that […]
Setting Reply-to Address in Pine
We often need to mail brief messages from servers to send config files, or quick messages to other sysadmins. Pine works well for this, and the installation is mostly a single binary. We usually are logged in on some account that isn’t the email address we wish replies to come to. It turns out that […]
Adding an Alias to Postfix
If you simply want to make a mailbox receive mail for another address, just add the full address to /etc/postfix/virtual: [root@srv-2 postfix]# cat virtual usr-1@networking.com usr usr-1@networking2.com usr usr-2@maildomain.com anotherusr If we simply add this line to the bottom: usr-3@maildomain.com anotherusr Mail that was was delivered previously via usr-2@maildomain.com will be delivered in the same […]
