Problem :
After ssh‘ing into a box and using yum or apt-get to patch, I would like to determine when a reboot is required. It would be incredibly helpful to know so we can schedule a reboot in a maintenance window.
Surprisingly, I did not find much reading on it. About the closest thing I found on a web search was How do I know if a reboot is required after patching? from Verizon, which effectively stated Linux does not usually need it because programs restart themselves (I suppose it was written for the average consumer).
I know Linux GUI’s offer it because, for example, the power button icon will turn red on Ubuntu/Unity. And I get prompted like below when logging in with a windows manager.
I regularly work with Debian, Ubuntu, Fedora, CentOS and Red Hat, so its the reason I listed yum and apt-get.
How do I determine when a reboot is required after patching?
Thanks in advance.
Solution :
In Debian-based OSes, the package manager will create a file, /var/run/reboot-required, if a patch requires a reboot. This file is deleted when the machine is restarted. See this AskUbuntu post for more information about how to determine which package required a reboot.
To get the same functionality in yum, it appears that you need to install a third-party plugin.