Timothy Murphy wrote: > My idea was that I could just "yum remove" and then "yum install" > to get back to the original position, > but I found that these operations are by no means mutually inverse, > as "yum remove" seemed to remove a whole range of packages > which for some reason I was not able to recover with "yum install". > Maybe "yum remove" should come with a health warning? Um. If package A works perfectly well as a program on its own, but packages B, C, and D depend on it (so you can either have just A installed, or A and some combination of B, C, and D), and you run yum remove A then B, C, and D will also have to be removed because they depend on it, and will no longer work. If you then do yum install A then yum won't know that you also want B, C, and D, because they aren't needed. Or, to put it mathematically, yum remove A removes the set of packages that are *dependent on* A (including A) yum install A installs the set of packages that A *depends on* (including A). "Depends on" is not symmetric, so "depends on" is not an equivalence relationship, and you don't get equivalence classes. But you can recover them by looking in /var/log/yum.conf, and seeing what was removed. Then use yum to reinstall them. Hope this helps, James. -- E-mail address: james | actor: (n) a piece of scenery that has the audacity @westexe.demon.co.uk | to move once lit.
