Glossary

This glossary covers terms and abbreviations that frequently appear in Enterprise Linux documentation.

A

ACL (Access Control List)

A more granular permission control mechanism than traditional Unix file permissions.

Anaconda

The system installer used by Red Hat family distributions.

Anolis OS

An EL-compatible distribution initiated by Alibaba and maintained by the OpenAnolis community, targeting cloud computing and data center scenarios with support for domestic architectures.

AVC (Access Vector Cache)

The access vector cache of SELinux. The type of log message produced when SELinux denies access.

C

CentOS Stream

The upstream development branch of RHEL. Receives updates slightly ahead of the corresponding RHEL version.

Cockpit

A web-based server management interface, available by default on EL 9.

D

DNF (Dandified YUM)

The default package manager for EL 8+, replacing YUM.

E

EL (Enterprise Linux)

A general term for the family of distributions built from or highly compatible with RHEL source code, including CentOS Stream, AlmaLinux, Rocky Linux, Oracle Linux, Anolis OS, OpenCloudOS, and others.

EPEL (Extra Packages for Enterprise Linux)

An additional software repository for EL maintained by the Fedora community, providing packages not available in official RHEL/EL repositories.

F

firewalld

The dynamic firewall management tool on EL systems, managing rules based on the concept of zones.

G

GRUB2

The bootloader used by EL systems.

J

journalctl

The log viewing tool for systemd, used to view logs collected by systemd-journald.

K

KVM (Kernel-based Virtual Machine)

A virtualization technology built into the Linux kernel, and the preferred virtualization solution on EL systems.

L

LVM (Logical Volume Manager)

Allows flexible resizing of partitions. The EL installer uses LVM partitioning by default.

N

NetworkManager

The default network management service on EL systems. The command-line tool is nmcli.

O

OpenAnolis

An open-source operating system community initiated by Alibaba that maintains Anolis OS.

OpenCloudOS

An open-source operating system community initiated by Tencent, targeting cloud computing scenarios and providing an EL-compatible distribution.

Oracle Linux

An EL-compatible distribution released by Oracle Corporation. Offers a choice of RHCK (RHEL Compatible Kernel) or UEK (Unbreakable Enterprise Kernel).

P

Podman

A daemonless container runtime and the replacement for Docker on EL systems. Its command syntax is largely identical to Docker.

R

RHEL (Red Hat Enterprise Linux)

The commercial Linux distribution released by Red Hat, and the origin of the EL family.

RPM (Red Hat Package Manager)

The low-level package format and management tool used by Red Hat family distributions.

S

SELinux (Security-Enhanced Linux)

A mandatory access control (MAC) security mechanism enabled by default on EL systems.

systemd

The init system and service manager used since EL 7+. The management tool is systemctl.

systemctl

The primary management command for systemd, used to start/stop services, view status, and more.

U

UEK (Unbreakable Enterprise Kernel)

A kernel exclusive to Oracle Linux, custom-optimized from the upstream Linux kernel, with support for Ksplice zero-downtime live patching.

X

XFS

The default filesystem type used by EL systems.

Y

YUM (Yellowdog Updater Modified)

The package manager from the EL 7 era. On EL 8+, the yum command is an alias for dnf.