New CentOS 8 Linux Release

The new CentOS 8 rebuild is out. Christened version 8.0-1905, this release provides a secure, stable and a more reliable foundation for CentOS users such as organizations running high-performance websites and businesses with Linus experts that use CentOS daily for their workloads, but who do not need strong commercial support.

The new OS comes in after Red Hat released RHEL 8 – Red Hat Enterprise Linux – in May of this year. According to CentOS 8 release notes, the contributors note that this rebuild is 100% compliant with Red Hat’s redistribution policy. This Linux distro allows users to achieve successful operations using the robust power of an enterprise-class OS, but without the cost of support and certification. Below are some of the updates as outlined in CentOS 8 release notes that you can expect with this new release and some of the deprecated features.

What’s New in the Just Released CentOS 8?

  • BaseOS and Appstream
  • New container tools
  • Systemwide crypto policies
  • TCP stack improvements
  • DNF

· BaseOS and Appstream

The main repository or Base Operating System offers the components of distribution that in turn provide the running user space on the hardware, virtual machines, or even a container. The Application Stream or App stream offers all the apps you might want to run in particular user space. The Supplemental repository offers software that comes with special licensing.

· New Container Tools

With the aid of Podman, CentOS 8 supports Linux Containers. This replaces Docker and Mobdy, which depend on daemon and run as root. Unlike the previous release, the Podman in the new version does not depend on daemon. Podman allows users to create images from scratch using Buildah.

· Systemwide Crypto Policies

The command “update crypto policies” can be used to update the system-wide cryptographic policy on the new OS. The policies have settings for the following applications and libraries; NSS TLS library, Kerberos 5 library, Open SSH SSH2 protocol implementation, IKE protocol implementation & Libreswan IPsec, Open SSL TLS library and GnuTLS TLS library.

· TCP Stack Improvements

The CentOS 8 Linux distro also brings with it TCP stack version 4.16 with an improved ingress connection rate. The Linux kernel is now able to support the new BBR and NV control algorithms. This is very helpful in helping improve the Linux server internet speed.

· DNF – Dandified Yum

The new Operating System includes the basic foundations of the Yum package but is now upgraded to the DNF (Dandified Yum). Though it maintains a similar command-line interface and API to its predecessor, it does promise to be faster, seamless and super-efficient.

· Other Improvements

The CentOS also has a compiler based on the version 8.2 and includes support for more recent C ++ language standard versions, improved optimizations, more code, and hardening techniques as well as new hardware support and better warnings.

In addition to those features, the new CentOS 8 also supports secure guests, which using cryptographically signed images will ensure that the program retains its integrity. It also boasts of improved management of memory and support. CentOS 8 release notes state that the new OS will allow the Crash dump to take in kernel crash during all booting phases which were not possible before.

CentOS 8 gives encrypted storage to LUKS2. It also allows for enhancements made to the process scheduler to include the new deadline process scheduler. This Linux distro will also enable installations and boot from dual-in-line, non-volatile memory modules.

A great bonus feature is that you can manage the new software with Cockpit via a web browser. This feature is very user-friendly, making it great for system administrators and new users alike.

Deprecated Features and Functionalities

If you are upgrading from previous CentOS versions, the most significant change is seen in the nftables framework which has replaced iptables. Nfatables allows users to perform network address translation (NAT) mangling, packet classification, and packet filtering. Unlike iptables, nfatables helps to provide secure firewall support with enhanced performance, increased scalability, and easy code maintenance.

These changes, though not major, may cause problems with firewall functionality. Although upgrades using RHEL may be supported, it is not advisable to upgrade directly from much older versions of CentOS like CentOs 6 and below as they may not be compatible.

Users of CentOS as a desktop will see an update of the GNOME SHELL default interface to version 3.28, while still carrying the default display server as Wayland.

Final Thoughts

If you are looking to upgrade from previous versions, a system to do so directly is yet to be released. As such, your most favorable option would be to back up your data as you install the newly released CentOS 8. When it is up and running, you can then move all the data to the new system.

Nonetheless, the new CentOS 8 Linux release is an exciting feat. This OS provides a manageable and consistent platform that suits a wide variety of deployments. It comes with well-thought-out and ingenious software updates that will help avid users to build more robust container workloads and web apps.

Useful Links – Linux

Here are a few useful references for Linux, which may be helpful.

Linux Documentation

Bash Documentation

Links for Major Linux Distributions

CentOS

Red Hat Enterprise Linux (RHEL)

Ubuntu

The most Important Linux Distributions To Learn Professionally

Many of us either want a way to import our Linux knowledge, improve our technical career options or perhaps, move into the technology career.  To do any of these efficiently them, the first step would be to focus on the major Linux distribution used by employers. 

The most adapted distributions Linux are Red Hat Enterprise Linux (RHEL) and Ubuntu, so, of the multitude of Linux distributions available, these would be the to learn if you want to move your career forward.

However, if you are seeking an inexpensive alternative to hone your Linux skills at home, then CentOS, is likely your best choice since it is free and is pretty much a copy of RedHat.

Related References

Best Linux Distros for Beginners

For those people who dip their toe into Linux systems for the first time, the endless options for distributions can be overwhelming, mainly when you are unsure for what to search. Just a few years ago when Linux was still in its early stages, this task would be much more comfortable as you could choose one of which you have heard about or have experienced. However, the increasing number of available distros and their vocal fans makes it challenging to settle on one.
So if you are new to this platform and don’t know where to start, here are top 5 best Linux distros for beginners to check out.

CentOS is a Linux distribution, which is derived from the sources of Red Hat Enterprise Linux and therefore has an obvious advantage for folks wanting to learn, improve, and practice their skills. Especially, since it is a free distribution and there are courses available to get you started on training sites like Udemy. the relationship between CentOS and Rehat make the skill and commands learn transferable since Redhat is a major Linux distribution us by businesses.

Ubuntu Linux

A list of Linux distros can’t be complete without the Ubuntu Linux. Indeed, most Linux distros come from Ubuntu simply because it is among the most user-friendly and stable ones available.
Just like other modern systems, Ubuntu Linux includes its app store named Ubuntu Software. You can find a collection of numerous apps to install. Though they might look entirely unfamiliar at the beginning, any mobile or computer user would learn how to use it quickly without a learning curve.
Ubuntu Linux comes with the installed software, which may include the web browser Firefox, office suite LibreOffice, webcam app Cheese, email client Thunderbird, and more.

Ubuntu Linux Pros

  • Easy to learn and use
  • Great support from the community
  • Quick to install and set up
  • Elegant and stylish design
  • Modern and user-friendly interface

Ubuntu Linux Cons

  • Ubuntu Linux has higher operating system requirements

Elementary OS

If you are a macOS user, then the Elementary OS Linux distro will be familiar. The developers try to create a global design that can make every element on the desktop feel and look similar for macOS users.


The Elementary OS desktop apps are launchable from the Dock or Applications menu. Power, network, notifications, and sound options are in the top bar, also known as the Wingpanel.
The AppCenter allows you to install essential applications to get your tasks done. Overall, Elementary OS is a great Linux distro for beginners and is simple to use.

Elementary OS Pros

  • Perfect hardware recognition
  • Minimalist interface resembling macOS
  • Simple to use
  • Ubuntu Foundation

Elementary OS Cons

  • A limited number of installed applications

Zorin OS

If you are a fan of Windows, the Zorin OS would be a great Linux distro for you. It comes with a familiar desktop interface that is gorgeous and simple to navigate. You can also switch to other interfaces to meet your tastes. These include GNOME3, Window XP, and Window 7.
Zorin OS is the only distro in this list designed with Windows users in mind. It includes Wine, a compatibility layer which makes it possible to install Windows apps on Linux. The distribution also integrates PlayOnLinux, a graphical app store to set up many Windows applications.

ZORIN OS Pros

  • Ideal for Windows users
  • An excellent collection of installed applications
  • Modern and elegant interface
  • You can change the interface to suit your preferences

ZORIN OS Cons

  • It takes time to learn

Linux Mint

Linux Mint is another Linux distro based on Ubuntu. Linux Mint offers 3 choices of desktops: Xfce, Mate, and Cinnamon. Each option has its pros and cons, but the Cinnamon is probably the best one for beginners.


This distro integrates familiar components on the desktop such as system tray, start button, or clickable icons. That’s why Linux Mint is an excellent option for those who are new to Linux.
Also, the Linux Mint is very lightweight as it only runs on 9 GB space of hard disk and 512 MB RAM. The lightweight footprint means you could load it up on an older PC and test before setting up on newer hardware.

Linux Mint Pros

  • Require low hardware
  • Great collection of default applications
  • Simple and user-friendly interface
  • Ubuntu Foundation

Linux Mint Cons

  • The interface is a bit old-fashioned

Ubuntu Budgie

Ubuntu Budgie is a gorgeous and straightforward Linux distro for beginners. Ubuntu Budgie has many new features on its Budgie desktop, such as the main menu, a dock, and a panel which includes notifications and some extras. Also, there are many other pre-installed apps to meet your needs, including LibreOffice, web browser Chromium, movie player GNOME MPV, webcam booth, and email.


Also, Ubuntu Budgie comes with a night light choice for those who often do plenty of work during the night and need to reduce the brightness. Ubuntu Budgie simplicity and beauty makes an impression.

Ubuntu Budgie Pros

  • Simple to learn
  • Ubuntu Foundation
  • The interface is gorgeous
  • Many default applications

Ubuntu Budgie Cons

  • Support could be unreliable

Conclusion

There are several things you should know about Linux distros:

  • You can download all of these distributions for free as .iso image files.
  • These distributions can be operated very well on most standard PC hardware, either laptops or desktops.
  • You need to burn ISO images to either a USB flash drive or CD/DVD.
  • It is possible to run all of these Linux distros as “live” instances, which means that you could boot your operating system from the flash drive or CD/DVD and run directly from the RAM of your PC without setting up anything.

Related References

8 Most Useful Linux Commands For Beginners

Do you think that the command lines are an old-fashion leftover from previous decades or an antiquated way of using a PC? Think again. Indeed, it is one of the most powerful and flexible ways to perform and manage in Linux. If you come from the comfort of a Mac or Window desktop, however, it can be a bit intimidating to get used to Linux commands. Everything is secretive, dark, and anything but friendly to beginners. That’s why we have rounded up this short list of the most useful Linux commands with examples. Keep reading and speed up your learning journey with Linux.

1. Ls command – list files

Ls is one of the most basic and common commands in Linux. You can use it to print contents in the current working directory and see the list of files, directories, or folders on your Linux system.
For instance, the command “ls tourism” will display the users every folder store inside the overall “tourism” folder. Keep in mind that directories and files will be denoted in different colors, which can be selected in the system.
You would also use the command “ls – R” to display all files both in the directories and subdirectories. Since Linux commands are case sensitive, make sure to enter “R” instead of “r” to avoid an error.

2. Cat command – create and view files

You can use the “cat” command to show text files. Also, it would be used for creating, combining, and copying text files. For example, use “cat linux_tip” to get inside the linux_tip file and read its contents on the screen.
To combine two text files “linux_tip_1” and “linux_tip_2, you can enter the following command “cat linux_tip_1 linux_tip_2 > linux_tip”. Keep in mind that only text documents would be combined and shown with this command.

3. Rm command – delete files

The “Rm” command can be used for removing files or directories from your Linux system without confirmation. The syntax is simple “Rm name_deleted_file.”
For example, the command “rm computer_science” will immediately remove the file or directory named “computer_science” from your computer. Make sure to consider carefully before using this command because you cannot get it back.

4. mv command – move and rename files

To move and rename files, the “mv” command will be used. Here is the basic syntax for this task: “mv filename new_location.”
Suppose that you need to move the file name “english_class” to location “/home/school/documents”, just enter the command “mv english_class /home/school/documents.” Keep in mind that this command requires the permission of users.
The syntax for renaming a file is “mv filename newname”. An example command is “mv english_class french_class”

5. Mkdir – create directories

If you want to create a new directory in your Linux system, then you can use the “mkdir” command. The syntax is “mkdir new_directory.”
For instance, you can create a new directory named “final homework” by typing the following command “mkdir final_homework.” In case you do not want to make a parent directory manually, add the -p argument. Keep in mind that it is -p, not -P. Everything in Linux is case sensitive.

6. Rmdir command – remove directories

In contrast with the mkdir command, you can use the rmdir command to remove a directory. The syntax is similar: “rmdir removed_directory.”
If you enter the following command “rmdir basketball_data”, it will immediately delete the directory named “basketball_data”. Always check carefully to make sure that there is no sub-directory or file under the deleted directory. If possible, it is always better to delete the sub-directory or files first before moving to the parent one.

7. Man command – seek help in Linux

“Man” simply stands for manual. You can use this command to access a reference book of the Linux system, which is quite similar to the “Help” file in many popular applications or software. To seek help on any commands that you don’t understand, just enter “ma command_name”. The terminal will open a manual page for the typed command.
For example, if you enter “man ls”, the terminal will provide you with basic information on the “ls” command.

8. History command – view previous commands

As you can guess from the name, the “history” command can be used to display all of the commands that you just used previously for the current session. This can be helpful in referring to the old commands and re-entering or re-using them in the next operations.

Related References

Linux – What is yum?

In simple terms, yum is a, command-line interface, package manager utility for computers running the Linux operating system, which augments the RPM Package Manager capabilities. yum is the primary tool for getting, installing, deleting, querying, and managing RPM software packages. Also, yum is used in Red Hat Enterprise Linux (RHEL) versions 5 and later.

Linux – how to display file system disk space statistics

In Linux there are lot of ways to disk size and/or space, but the ‘Disk Filesystem’ (df) command is old reliable and has been around a long time.   The ‘df’ command provides a summary of disk space and free space, which I find myself coming back to time after time.

Basic Command Format

DF -<<Option>>   <<File>>

Example ‘Disk Filesystem’, Command

df -h

  • -h = Human readable in MegaBytes

For more details in Linux

df –help

Example Command Output

root@BlogSrvr1 /]# df -h

Filesystem            Size  Used Avail Use% Mounted on

/dev/mapper/vg_BlogSrvr1-lv_root

36G   34G   16M 100% /

tmpfs                 3.9G     0  3.9G   0% /dev/shm

/dev/sda1             477M   33M  419M   8% /boot

/dev/mapper/vg_BlogSrvr1-LogVol03

11G   27M  9.9G   1% /data

/dev/mapper/vg_BloSrvr1-lv_home

4.8G   33M  4.6G   1% /home

/dev/mapper/vg_BlogSrvr1-LogVol04

25G   13G   11G  55% /opt/IBM

/dev/mapper/vg_BlogSrvr1-LogVol05

11G  6.0G  3.7G  62% /scratch

/dev/mapper/vg_BlogSrvr1-LogVol06

11G   27M  9.9G   1% /tmp/dev/shm