Introduction
At certain times after a cPanel update, you might come across a notification in the top right portion of your WHM, asking you either "You must reboot the server to apply kernel updates." or "You must reboot the server to apply software updates." or both.
Procedure
To assist with identifying why you might require a reboot can be done with our internal WHM API Feature. You can run the following command via SSH or in the WHM Terminal:
# whmapi1 system_needs_reboot
Example Output:
cPs# whmapi1 system_needs_reboot
---
data:
details:
kernel:
updates:
linux-firmware: 20191203-76.gite8a0f4c.el7
systemd: 1:219-73.el7_8.9.cloudlinux
needs_reboot: 1
metadata:
command: system_needs_reboot
reason: OK
result: 1
version: 1
Above we can see the RPM's are listed for each service that might require new updates to the RPM. You can proceed with the reboot by selecting the notification in your WHM. And invoking a "Graceful Reboot" of your server.
Here is more information on how can update various parts of your cPanel & WHM server: https://docs.cpanel.net/knowledge-base/general-systems-administration/how-to-update-your-system/