derivatives: Fedora, Rocky, Alma, CentOS
Red Hat Enterprise Linux operating system freezes the Fedora a year or two before its release
CentOS Project is an community fork of RHEL, like a beta stream sitting between Fedora and Redhat
Fedora is the official open source version of RHEL, bleeding edge, test ground for RHEL features
Rocky Linux binary‑compatible rebuild of RHEL by original CentOS creators
AlmaLinux OS - Forever-Free Enterprise-Grade Operating System another binary‑compatible rebuild of RHEL
Fedora
Package Management: RPM (dnf after 22)
Fedora (operating system) - Wikiwand
FedoraProject
The Fedora Project history and family tree - Fedora Magazine
The relationship between Fedora and Red Hat Enterprise Linux | Red Hat
Fedora 21 rolls three versions of Linux into one OS | InfoWorld
Fedora 25 stakes out leading edge, not bleeding edge | InfoWorld
Rawhide is the Fedora's rolling release
Releases/Rawhide - FedoraProject
Nobara Project
I Love Nobara Linux - Goodbye Manjaro and Distro Hopping - YouTube
CentOS
Firewall
CentOS Linux 7 以 firewalld 指令設定防火牆規則教學 - G. T. Wang
How To Open A Port In CentOS / RHEL 7 – The Geek Diary
5.3. Viewing the Current Status and Settings of firewalld Red Hat Enterprise Linux 7 | Red Hat Customer Portal
Open firewall port on CentOS 7 - Stack Overflow
Package manager
DNF Package Manager For RPM-Based Linux Distributions - LinuxAndUbuntu - Linux News | Apps Reviews | Linux Tutorials HowTo
what is different between DNF and yum [Quick review] - Eldernode
DNF command on CentOS 8 - what is DNF command - DNF tutorial
EPEL (Extra Packages for Enterprise Linux): AUR for CentOS
Top 8 YUM ThirdParty Repositories for CentOS and RHEL
RPM Fusion supplies legal, patent-encumbered multimedia codecs, drivers, and non-free software.
EPEL (Extra Packages for Enterprise Linux) and RPM Fusion are complementary, third-party repositories for RHEL/Fedora clones (Rocky, Alma, CentOS). EPEL provides high-quality, open-source server/system tools not in base repos.
Copr
Category:Copr - FedoraProject
Copr Plugin | DNF
Fedora Hosted is Fedora's equivalent of AUR or PPA, it hosts many Copr (Cool Other Package Repo).
FAQs - Fedora Hosted
UserDocs – copr
HowToEnableRepo – copr
sudo dnf copr enable <reponame>
# for remix such as Korora, specify Fedora base
sudo dnf copr enable <reponame> fedora-23-x86_64Fedy
Fedy - Tweak your Fedora
folkswithhats/fedy: Fedy lets you install multimedia codecs and additional software that Fedora doesn't want to ship, like mp3 support, Adobe Flash, Oracle Java etc., and much more with just a few clicks.