Matthew Miller (mattdm@fedoraproject.org) said:
I'm a little lost in the thread, but do you mean that yum's protected packages functionality is undocumented? If that is what you mean, check the man page. It says:
protected_packages This is a list of packages that yum should never completely remove. They are protected via Obsoletes as well as user/plugin removals.
The default is: yum glob:/etc/yum/protected.d/*.conf So any packages which should be protected can do so by including a file in /etc/yum/protected.d with their package name in it.
Also if this configuration is set to anything, then yum will protect the package corresponding to the running version of the kernel.
While documented, I do find this last bit of behavior extremely odd and non-intuitive. (And hardcoded, no less.)
Bill