How to check if a host needs to reboot?

Hello Community,

I'd like to know how to figure out if a host needs to be rebooted after the installation of updates. Is there any way to determine wether a reboot is needed or not?

By know I could use the following script to create a file if a reboot is necessary:

#!/bin/bash
LAST_KERNEL=$(rpm -q --last kernel | perl -pe 's/^kernel-(\S+).*/$1/' | head -1)CURRENT_KERNEL=$(uname -r)

if [[ ! $LAST_KERNEL = $CURRENT_KERNEL ]];
then
  touch /var/run/reboot-required
fi

But I'm not sure if a new kernelversion is the only reason that requires a reboot.

On SLES there is the command

zypper ps -s

Kind regards,
Joerg