RHEL, Its Relatives and SUSE
A company's older servers run Red Hat Enterprise Linux, and the new database cluster runs SUSE. You type apt install out of habit and get "command not found". Nothing is broken; you are simply talking to a different family.
The rule
Red Hat speaks rpm and dnf; SUSE speaks rpm and zypper.
RHEL (Red Hat Enterprise Linux) is a commercial distribution sold with a support subscription, popular in banks, governments and large companies. Around it sits a family:
- Fedora: the fast-moving community distro where new ideas are tried first.
- CentOS Stream: a preview of the next RHEL minor release.
- Rocky Linux and AlmaLinux: free rebuilds designed to be compatible with RHEL.
They all use .rpm packages and the dnf tool, which replaced the older yum. On current releases, typing yum still works because it is kept as a compatible alias.
SUSE Linux Enterprise and the community openSUSE also use .rpm packages, but their tool is zypper.
Two other differences catch newcomers on RHEL-family servers:
- The firewall is usually managed with
firewall-cmd(firewalld), where Ubuntu often usesufw. - SELinux is on by default. It can block a service from reading files or opening ports even when normal file permissions look correct.
The shortcut
Keep a translation table in your head. The verbs are nearly the same; only the tool name changes:
| Task | Debian / Ubuntu | RHEL family | SUSE |
|---|---|---|---|
| Install | apt install nginx |
dnf install nginx |
zypper install nginx |
| Upgrade all | apt upgrade |
dnf upgrade |
zypper update |
| Search | apt search nginx |
dnf search nginx |
zypper search nginx |
| Package file | .deb |
.rpm |
.rpm |
Service management is the same everywhere thanks to systemd: systemctl start, stop, restart, enable, status.
Identify
/etc/os-releaseshowsID="rocky"andID_LIKE="rhel centos fedora".
The trap: the service starts but cannot reach its files or port, and permissions look fine. On the RHEL family, suspect SELinux and check the audit log before loosening file permissions.
Drills
Answer fast — trust the rule.
Which command installs nginx on a Rocky Linux server?
What package format do RHEL and SUSE share?
On an openSUSE server, which tool manages packages?
On RHEL, nginx is running but cannot read a folder even though chmod looks right. What should you suspect first?
Remember
- Red Hat speaks rpm and dnf; SUSE speaks rpm and zypper; Debian speaks deb and apt.
- Shortcut: same verb, different tool; systemctl is the same everywhere.
- Trap: forgetting firewalld and SELinux on the RHEL family.