Network scripts are deprecated in Red Hat
Enterprise Linux 8 and they are no longer provided by default. In Red
Hat Enterprise Linux 8, to run the ifup and the ifdown scripts,
NetworkManager must be running. By default if you try to use legacy
network.service unit file is not available with RHEL 8.
Control the running service with systemctl start, stop, or restart; see the systemctl command for try-restart and dependency behavior.
[root@rhel-8 ~]# systemctl restart network
Failed to restart network.service: Unit network.service not found.
You can use "NetworkManager.service" as the default networking service
in RHEL 8. Red Hat Enterprise Linux 8 uses the default networking
service, NetworkManager, which is a dynamic network control and
configuration daemon to keep network devices and connections up and
active when they are available.
Starting Network Service with NetworkManager
To start NetworkManager:
[root@rhel-8 ~]# systemctl start NetworkManager
To enable NetworkManager automatically at boot time:
[root@rhel-8 ~]# systemctl enable NetworkManager
Start Network Service without NetworkManager
If you use NM_CONTROLLED=no in ifcfg file then you will be unable to
bring up interfaces with 'ifup' command.
The basic installation of RHEL 8
provides a new version of the ifup and ifdown scripts which call the
NetworkManager service through the nmcli tool.
/sbin/ifup-local, ifdown-pre-local and
ifdown-local scripts are not executed.
How to fix Failed to restart network.service: Unit network.service not found in RHEL 8
If any of these scripts are required, the installation of the deprecated network scripts in the system is still possible with the following command:
Package installs and updates in this section use dnf command.
[root@rhel-8 ~]# yum install network-scripts
In RHEL 7 /etc/rc.d/init.d/network was owned by initscripts but with
RHEL 8 this tool is part of network-scripts rpm
Next you can check the content of network-scripts rpm
List files owned by a package with rpm -ql; the rpm command helps locate binaries and config paths on RHEL-family hosts.
[root@rhel-8 ~]# rpm -ql network-scripts-10.00.1-1.el8.x86_64 | grep "/etc/rc.d/init.d/network"
/etc/rc.d/init.d/network
The ifup and ifdown scripts link will be installed with legacy
network scripts.
Calling the legacy network scripts shows a warning about their deprecation.
[root@rhel-8 ~]# ifup eth0
WARN : [ifup] You are using 'ifup' script provided by 'network-scripts', which are now deprecated.
WARN : [ifup] 'network-scripts' will be removed in one of the next major releases of RHEL.
WARN : [ifup] It is advised to switch to 'NetworkManager' instead - it provides 'ifup/ifdown' scripts as well.
Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/6)
Now you can use systemctl to restart the network service
[root@rhel-8 ~]# systemctl restart network
[root@rhel-8 ~]# systemctl is-active network
active
Lastly I hope the steps from the article to fix "Failed to restart network.service: Unit network.service not found"in RHEL 8 Linux was helpful. So, let me know your suggestions and feedback using the comment section.

