RHEL/Rocky/Alma

Enterprise-grade Linux distributions focused on stability, long-term support, and enterprise features.

Distribution Overview

Distribution Base Support Use Case

RHEL

Fedora

10+ years

Commercial enterprise

Rocky Linux

RHEL source

10 years

CentOS replacement (community)

AlmaLinux

RHEL source

10 years

CentOS replacement (CloudLinux)

CentOS Stream

RHEL development

5 years

RHEL preview/dev

Post-Install Essentials

Update System

sudo dnf upgrade --refresh

Essential Packages

sudo dnf install vim-enhanced tmux htop git wget curl tar
sudo dnf group install "Development Tools"

Enable EPEL

Extra Packages for Enterprise Linux:

# RHEL 9
sudo dnf install https://dl.fedoraproject.org/pub/epel/epel-release-latest-9.noarch.rpm

# Rocky/Alma 9
sudo dnf install epel-release

# Verify
dnf repolist | grep epel

Configure SELinux

Check status:

getenforce
sestatus

Common operations:

# Set permissive temporarily
sudo setenforce 0

# Set enforcing
sudo setenforce 1

# Permanent change in /etc/selinux/config
sudo sed -i 's/SELINUX=enforcing/SELINUX=permissive/' /etc/selinux/config

System Information

# OS version
cat /etc/redhat-release

# Detailed info
cat /etc/os-release

# Kernel
uname -r

# Check subscription (RHEL only)
subscription-manager status

Firewall Configuration

# Status
sudo firewall-cmd --state

# List current rules
sudo firewall-cmd --list-all

# Open port permanently
sudo firewall-cmd --permanent --add-port=8080/tcp
sudo firewall-cmd --reload

# Open service
sudo firewall-cmd --permanent --add-service=http
sudo firewall-cmd --reload

Maintenance

Clean Package Cache

sudo dnf clean all
sudo dnf autoremove

Check for Security Updates

sudo dnf check-update --security
sudo dnf upgrade --security

System Health

# Failed services
systemctl --failed

# Journal errors
journalctl -p err -b

# Disk usage
df -h

Pages

See Also