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CentOS 8 part A

You Might All Hear About The New Update Coming To Centos, Which Goes By The Name Of Centos 8, After Releasing This Update There Many Rumors About It And How It Is Gonna Affect The User Experience, With The Interface, In, Some Cases, Around The Command Lines In The Terminals, Today In This Article We’re Gonna Take A Better Look At Its New Features And Changes Within The Centos 8.

After the introduction of the Linux OS in 2004, all of the people that consider themselves possible to use this new operating system knew at first glance what is the idea of publishing and developing so many different distros, which was to provide the user with a unique interface and features both in design and utility, each distro for one person or groups of users.

At first, the primary purpose of the developer for publishing so many distros was to take a step ahead of Microsoft company and the Windows OS. Still, as time passed, they started to realize that the fame caused by Microsoft can’t fade away that simply, and they focused all of their attention and effort on developing and improving their distros, with counter the result of it that we know by the name of CentOS.

This article details what awaits you in the new and fresh breath infused into CentOS 8. We will look at what you should expect when CentOS 8 purrs on your server or desktop for the first time.

Desktop

  • The GUI version of CentOS 8’s GNOME Shell has been rebased to version 3.28.

Unlike so many users who are truly happy about this update change to the desktop environment, on the other hand, we have some mad users who can’t get along with this change; lucky for those who aren’t okay with this change, they can also downgrade to the last version of it, but in one condition that they have to have an updated CentOS 8.

  • The GNOME session and the GNOME Display Manager use Wayland as their default display server. If you are a XORG person, do not panic; the X.Org server, the default display server in CentOS/RHEL 7, is also available.

: Wayland happens to have the following features

  • The desktop can control window handling directly
  • Stronger security model
  •  Multi-monitor handling

 Networking

  • The nftables framework has replaced iptables as the default network packet filtering facility.
  • The firewall daemon now uses nftables as its default backend.
  • NetworkManager now supports single-root I/O virtualization(SR-IOV) virtual functions (VF). NetworkManager allows configuring some attributes of the VFs, such as the MAC address, VLAN, the spoof checking the setting, and allowed bitrate.
  • CentOS 8 is distributed with TCP networking stack version 4.16, which provides higher performances, better scalability, and more stability.
  • Support for IPVLAN virtual network drivers enabling network connectivity for multiple containers.

Language, server, database

In the update CentOS 8, you’ll encounter Python 3.6; you don’t have to worry cause it includes Python 2.7, too; with all of it being said, no version of Python is installed by default, so in this part, you might want to download it yourself.

Web Servers: Apache HTTP Server 2.4 and introduction of Nginx 1.14.
Squid has been updated to version 4.4, and a new proxy caching server is now included: Varnish Cache 6.0. Database servers distributed with CentOS/RHEL 8: MariaDB 10.3, MySQL 8.0, PostgreSQL 10, PostgreSQL 9.6, and Redis 5.

Software

The YUM package manager is now based on the DNF technology, and it provides support for modular content, increased performance, and a well-designed stable API for integration with tooling; installing software is now ensured by the new version of the YUM tool, which is based on the DNF technology (YUM v4). CentOS 7 used YUM v3.

Enhancements made on YUM v4:

  • Full support for modular content
  •  Greatly increased performance
  • Well-designed stable API for integration with tooling

You can use the yum command and its particular options in the same way as on CentOS 7. Another thing worth mentioning is that CentOS 8 is distributed with RPM 4.14, which is different from the previous RPM 4.11 with more enhancements added.’

The most notable changes include the following:

  • Simplified signature checking the output in non-verbose mode
  • Additions and deprecation in macros
  • Stricter spec-parser

Image creation

CentOS 8 uses the Anaconda installer, which now supports the LUKS2 disk encryption format. LUKS2 offers better features; for instance, it extends the capabilities of the on-disk format and provides flexible ways of storing metadata. Anaconda has been extended to handle all features related to application streams. These include modules, streams, and profiles. Kickstart scripts can enable module and stream combinations, install module profiles, and install modular packages.

Kernel

: CentOS 8 is based on Fedora 28 and upstream kernel 4.18. Available on this Kernel

  • Spectre V2 mitigation default changed from IBRS to Retpolines – For cases where complete Spectre V2 mitigation is desired, a user can select IBRS through the kernel boot line by adding the spectre_v2=ibrs flag.
  • The I/O memory management unit (IOMMU) code in the Linux kernel has been updated to support 5-level page tables.
  • Intel Omni-Path Architecture (OPA) host software is fully supported in CentOS 8.