The firewall is a vital component of any Linux distribution. This is even more important when running a server versus a desktop distro. Firewalls are necessary since they protect a computer system or a network of computers from an external attack especially in a server environment where the server is connected to the Internet in an always-on Internet connection.

There are a couple of CLI tools that can be used to benchmark an HDD (external or internal). These are dd and hdparm. However, for Debian Linux, there’s a great GUI application that performs Disk Read speed benchmarking and both Disk Read & Write speed benchmarking if the drive being tested is unmounted. The dd command is used to monitor the writing performance of a disk device on a Linux and Unix-like system. An example for testing an internal SSD would be: 

$ sudo dd bs=1M count=256 if=/dev/zero of=test 

By default, Ubuntu 20.04 LTS is developed with a highly customized Gnome3 desktop which looks very much like the original Unity desktop. Many people, including myself, do not like the look and feel of this desktop even though it is based on the Gnome3 desktop environment. I am assuming that you are familiar with both Linux, the Linux Terminal, and have used Ubuntu Linux in the past. If you don’t meet these prerequisites, then you may find some of the steps in this conversion process to be a little confusing.

Linux handles file and folder permissions differently than operating systems like Microsoft Windows. Unlike file and folder permissions in the Windows world, Linux does not have what Microsoft Windows refers to as “effective” permissions on files and folders. True, one can change basic permissions on file objects in Linux using Access Control Lists (ACLs) or more appropriately File Access Control Lists (FACLs), but the point of this article is to introduce the new Linux user to the basic file and folder permissions that Linux uses when these objects are created in the system.

What is a stack and why is it important in Linux or Computer Science, for that matter? A stack, in the context of this article, refers to a last-in-first-out (LIFO) list or more affectionately referred to as a pushdown store. This is in contrast to another arrangement called first-in-first-out (FIFO) used in granaries since the grain is loaded at the top of the tower and dispensed at the bottom into trucks or other vehicles for delivery to its destination.

There is a feature built into ZFS called the “hotspares” feature which allows a sysadmin to identify those drives available as spares which can be swapped out in the event of a drive failure in a storage pool. If an appropriate flag is set in the feature, the “hot spare” drive can even be swapped automatically to replace the failed drive. Or, alternatively, a spare drive can be swapped manually if the sysadmin detects a failing drive that is reported as irreparable. 

Hot spares can be designated in the ZFS storage pool in two separate ways: 

Is it possible to configure a server such that one can ssh into that server internally on a LAN while being able to ssh into the network interface that communicates on the WAN out to the Internet? How do we handle this? Do we just open port 22 for ssh for both LAN and WAN and call it a day? Is this going to pose a security risk by allowing port 22 traffic from the WAN internally to our LAN? Can we even do this? The answer to this question is, YES! How can we take care of this without posing an unnecessary risk on our server? The answer to this second question is simple.

In this article, I want to explain the importance of being able to foreground and background a process running in Linux. If you’ve never used this technique or have never heard of it, then you will be happy to learn that it exists on all Linux distros and making use of it can really enhance your productivity and workflow.

We were pleased to present a member of the WNCLUG-Asheville, Pat Barnes, who gave

Linux bash aliases are like personal shorthand we can use in a Linux terminal. Aliases let us create abbreviations of a few characters to represent an entire Linux command, or even several of them. Think of bash aliases as command line macros for Linux.

For instance, here’s an alias to print a sorted list of shell environmental variables: