Click here for "Safe Air Conditioner Repair and Proper Freon Recovery".

RockyLinux 9 ; Various settings after installation

1.Disabling SELinux

First, disable selinux. selinux is a feature that improves auditing and security in Linux, but when enabled, it places considerable restrictions on the behavior of services and on what can be configured. Therefore, it is basically disabled in many cases.
SELinux operating modes
Enforcing : SELinux functionality is enabled and access control is enabled
Permissive : SElinux will warn, but no access restrictions will be placed
disabled : Both SElinux function and access control are disabled

①Current SELinux status

②Switching to [permissive] mode
③Switching to [enforcing] mode
④To completely disable SELinux, a reboot is required by adding selinux=0 to the kernel command line as follows

※ To return SELinux to active, do the following (reboot after changes)

2.System Modernization

Package updates are performed as soon as possible immediately after OS installation.
However, when a dnf update is performed, a kernel update is also performed at the same time.
A kernel update may require rebooting the system or stopping services, or worse, a kernel panic may occur and the system may not boot. It is wiser to exclude the kernel from the update.
The kernel can be excluded from updates by running dnf -y update with "--exclude=kernel*" after it.

3.Services to be stopped due to security measures

4.Adding Repositories

4.1 Add EPEL repository

4.2 Added Remi's RPM repository

5.Network Settings

5.1 Check network device name

The network device name can be found as "ens160"

5.2 Host Name Change

Change the host name to Lepard to try it out

5.3 Static IPv4 address configuration

The name of the network interface is "ens160" from 5.1
In Rockylinux8, this could be changed by rewriting the ifcfg-xxx file found in network-scripts, but in Rockylinux9
directory is empty and this method cannot be used, so use the "nmcli" command to change it.
Change the static IPv4 address to "".

Change by "nmcli" command

5.Vim Configuration

①Vim install

②Apply and reflect Vim
③Configure Vim as a user-specific environment