Superseded packages available on line? If not why not?

[ubergeeknz]

I am pretty new to the Ubuntu world, although I have flirted with Linux several times over the past 7-8 years. Ubuntu Feisty is the first time I have successfully managed to replace Windows (almost) entirely for my everyday work.

However I have a beef with the on line repository system.

If I get an update, and that update causes a problem (or I have cause to believe that it has), it seems that any time I go looking for the previously installed version of the package it is not available. Same goes for older kernel modules/source. Basically if I want to run anything less than the bleeding edge, I have to never update anything, which is obviously not desirable, or I have to fish out my CD and downgrade to the original version. This doesn't leave a lot of options open for troubleshooting.

Is there any good reason that all packages are not kept on line, even if they are superseded? is this a space issue? Or are there special repositories I need to add to get access to older packages? If no-one is doing this now, perhaps I could assist with getting this happening (I am sure I could find some inexpensive space).

If this was cleared up, I'd be really stoked. The Ubuntu community has, to my mind, tied up a lot of little loose ends that have been holding Linux back from widespread adoption for far too long. Keep up the good work!!

[moore.bryan]

most will tell you downgrading (or rolling-back) a package is a bad idea because of how it can screw-up post-installation scripts. all the "old" packages are available in the older repos (http://packages.ubuntu.com/), though; aren't they? you could (although, once again, i wouldn't recommend it) go to the breezy release and download/reinstall the old program...

[ubergeeknz]

Appreciate the quick and detailed reply!

most will tell you downgrading (or rolling-back) a package is a bad idea because of how it can screw-up post-installation scripts.

Fair enough; but isn't that a weakness in the packages or the packaging system that should be addressed? I mean any system destined to be used for anything resembling mission-critical systems surely must have a robust rollback for updates in case they cause issues. I suppose a clean removal of the package followed by a reinstall of the older package might do the trick, but really it should be transparent.

all the "old" packages are available in the older repos (http://packages.ubuntu.com/), though; aren't they?

I will try adding that repo next time I need to back something out, it might save me in a pinch (assuming it really does have all the superseded packages) :)

[moore.bryan]

Appreciate the quick and detailed reply!
Fair enough; but isn't that a weakness in the packages or the packaging system that should be addressed? I mean any system destined to be used for anything resembling mission-critical systems surely must have a robust rollback for updates in case they cause issues. I suppose a clean removal of the package followed by a reinstall of the older package might do the trick, but really it should be transparent.
i don't know if i'd classify it as a "weakness," but i do think having a set rollback program would be a good idea. alas, i am no programmer. ;-)
I will try adding that repo next time I need to back something out, it might save me in a pinch (assuming it really does have all the superseded packages)
i wouldn't add the repos, if i were you; instead, i'd just download the package i want to reinstall, download that deb and install it.

[venky]

Also see /var/apt/archives