How to Prevent Outgoing Spam on Your Server

Often when we think of spam, it usually relates to incoming spam inundating mail servers and bogging down systems. Another way spam can harm your dedicated server is from the inside.
Many spammers do not setup their own servers or paid hosting accounts to send spam. They want to be anonymous. Therefore, they often use other […]

How to Create Mail Aliases in Webmin

Webmin is a free and open source system management panel that can handle Unix and Linux system administration on dedicated servers in general and on web hosting servers in particular. You can use it to automate many of the server tasks that would normally require command line work, and creating mail aliases is one of […]

Troubleshooting High Mail Server Loads

These days many personal email accounts are hosted on cloud servers, leaving many web servers without the need to send and deliver emails to their users. For plenty of businesses, however, having a mail server is still very much a part of the dedicated server experience.
If you host your own mail server, whether Postfix, Sendmail, […]

How to Fix an Open Relay

According to, an open relay is “a mail server that does not verify that it is authorised to send mail from the email address that a user is trying to send from. Therefore, users would be able to send email originating from any third-party email address they want.”
Using an open relay, someone could […]

How to Control Linux Services

A service or daemon is a memory-resident program that runs in the background. Your operating system will typically start it at boot (although not always) and continue to run it without any intervention on your part. Some common services usually running on a Linux dedicated server are: web server (such as Apache), database […]

Mail Server Email Aliases

An email alias is a name that appears before the @ symbol in an email address, which actually refers to another account or location. For example, the alias “billing” may actually point to an email account on your server called “sales”. A single email account can have multiple aliases, and an alias can […]

How to Change the Port Number in Postfix

The default network SMTP port for Postfix, Sendmail and most other mail servers is 25. This is the port used to send email, and most email clients will use it by default. Unfortunately, some Internet service providers have started to block port 25 because of the high volume of spam sent through it. […]

Some Common Server Port Numbers

A dedicated server, particularly one running Linux, has a standard set of ports that are configured to operate with certain applications. By default, most firewalls, even when they are secured, allow the default ports to send and/or receive information to and from the outside world. It is still important to know what their […]