Upgrading Red Hat Enterprise Linux / CentOS / Oracle Linux
RHEL/CentOS/Oracle Linux Migration:
Network services came under the control of systemd with RHEL 7, making xinetd redundant. Samba has been greatly improved with the release of its version 4, and the old web-based administration tool has been dropped due to many security holes and very little maintenance. Services like Apache and BIND have been through several upgrades.Previous: Networking
The previous page explained the many changes in networking, including changes in network interface names and in the networking commands. It also described how Red Hat has been pushing their firewall daemon for access control.
9 — Networking: Network Services, and
10 — Print and File Service
For RHEL 6, see the earlier
of the media split into DVD1 and DVD2.
If you want
and several other network servers, you will need to get
the packages from DVD2 in RHEL 6.
Better yet, add the CentOS.org YUM respository and install things from there.
RHEL 7 includes an update to Samba 4, meaning that your Linux server can function as a full Active Directory server.
That also means that you can no longer use SWAT or the browser-based Samba Web Admin Tool. It was removed at Samba version 4.1 due to security concerns.
Apache updates to version 2.4.37 with RHEL 8
and 2.4.51 with RHEL 9.
HTTP/2 is now provided by the
module, part of the
The ACME protocol for automated TLS provisioning and
renewal is supported starting with RHEL 8,
so you can easily use Let's Encrypt certificates.
The MPM or multi-processing module used by default with
RHEL 8 has changed from
to the higher performance
Or, you can simply use the included Nginx web server and proxy included with RHEL 8 and later.
RHEL 8 supports TLS 1.3 with both Apache and Nginx, and in its back-end crypto libraries.
RHEL 9 includes OpenSSL 3, a huge redesign.
OpenSSH updates from 7.4p1 to 7.8p1 going from RHEL 7 to 8, dropping support for:
- SSH protocol 1.
- Host DSA keys, although user DSA keys are still supported.
- Ciphers arcfour, arcfour128, arcfour256, blowfish-cbc, cast128-cbc
- MAC algorithms hmac-ripemd160, email@example.com, firstname.lastname@example.org
RHEL 8 / OpenSSH 7.8p1 adds support for these key exchange algorithms: gss-group14-sha256-, gss-group16-sha512-, gss-nistp256-sha256-, gss-curve25519-sha256-
RHEL 9 has OpenSSH 8.7p1, with further changes to increase the security of default behavior.
See the OpenSSH Release Notes for full details.
The NTP service changed from classic
some time after RHEL 6.0.
That is, the initial RHEL 6.0 had
but it was replaced by
in a later 6.x release.
RHEL 8 dropped
That will challenge sites using
to meet extensive banner requirements.
tftp were the only
left in RHEL 7, everything else runs as a standalone
(Except for some truly antiquated services like
discard that was included
Verify this with:
# cd /path/to/package/files # for P in * > do > echo $P $( rpm -qlp $P 2> /dev/null | grep '/etc/xinetd.d' ) | grep '/etc/xinetd.d' > done
Even those were gone with RHEL 8.
You can write your own
but none is provided from Red Hat.
NFS service configuration changes significantly going from RHEL 7 to 8.
The kernel itself continues to evolve rapidly. Added features, improved performance, and bug fixes. But the way you configure a kernel hasn't changed much.
Clusters, on the other hand, work completely differently when you move from RHEL 6 to 7.
Next ❯ Kernel & Clusters