What is the Linux Kernel and What Does It Do?

A kernel is the lowest level of easily replaceable software that interfaces with the hardware in your computer. It is responsible for interfacing all of your applications that are running in “user mode” down to the physical hardware, and allowing processes, known as servers, to get information from each other using inter-process communication (IPC).

Upgrade to the Latest Ubuntu the Easy Way

Ready to jump on the latest Ubuntu, but don’t want to mess up your current Ubuntu installation?  Here’s how you can painlessly upgrade to Ubuntu 10.10, or any later normal release of Ubuntu, directly from the Update Manager.

How to Setup a VPN (PPTP) Server on Debian Linux

VPN-ing into your server will allow you to connect to every possible service running on it, as if you were sitting next to it on the same network, without individually forwarding every port combination for every service you would like to access remotely.

How to Backup Your Linux PC with Simple Backup

It doesn’t matter if you are using Windows, OS X, or Linux, everyone should do regular backups of their information. In Linux one of the easiest ways to do automated backups is with Simple Backup (SBackup). Here is how you can set up SBackup to make sure you have a backup of all your important files.

3 Easy Ways to Connect to Windows Shared Folders from Linux

Connecting to file servers is something most people do on a daily basis even without thinking about it. In Linux, it may not be intuitive how to quickly connect to a samba or ftp server without a separate program. Here are a few different ways to connect to a remote file server without needing to touch a terminal.

How to Setup milter-greylist Spam Blocking in Sendmail

Virtually all linux distributions include sendmail as the default MTA. Which is okay – it has been around for a long time, is stable and it works great (although the postfix afficionados might disagree!). But it has nothing built in for spam control which is good; it was not designed for that. So you’ve installed spamassassin and it works good but you still are getting unflagged spam emails through. Perhaps you need to try greylisting.

How to Prevent Yum from Updating the Kernel

When you’re running production servers, the one thing you don’t want to do is upgrade the kernel every time a new update comes out. Why? Because that’s the only Linux update operation that requires a reboot once it’s done—and in a production environment you often can’t have downtime.

How to Change Your Linux Hostname Without Rebooting

If you’ve worked in the admin world for any length of time, you’ve probably run into an instance where you needed to change the hostnames on your server to match some corporate naming standard, but you can’t have downtime either. So how do you change the hostname without rebooting?