To check if a CentOS or RHEL system needs a full reboot, you can use the needs-restarting command. This command is part of the yum-utils package and checks for updates to certain system components that require a full reboot to apply.
To check if a CentOS or RHEL system needs a full reboot, log in to the system as the root user and run the following command:
needs-restarting
If the system needs a full reboot, the needs-restarting command will display a list of system components that need to be restarted.
For example, the output might look something like this:
Kernel 4.18.0-147.8.1.el8_1.x86_64
In this example, the kernel has been updated and requires a full reboot to apply the changes.
If the needs-restarting command does not display any output, it means that the system does not require a full reboot.
It's worth noting that the needs-restarting command only checks for updates to certain system components, such as the kernel, system libraries, and system daemons. It may not detect updates to other components that require a full reboot, such as firmware updates or hardware changes.
To check for updates to all system components, you can use the yum command with the check-update option. This will display a list of available updates for the system.
For example, to check for updates to all system components, you can use the following command:
yum check-update
If the yum command displays any updates, it means that the system may require a full reboot to apply the changes. However, it's worth noting that not all updates require a full reboot, and you should consult the documentation for the update to determine if a full reboot is necessary.