When to reboot after auto-update

[nvanvliet]

Hi,

This maybe a newbie question, but I am new to Centos.

I have installed auto-update and it works fine. It sends me an email every time it has updated.
My question is how i can know that I need to reboot after an auto-update, (think of a security update for the kernel).

I am used to Ubuntu. There a message is displayed in the terminal if you login.

Thanks,
Nico