Checking /usr/local/ before upgrading

[Vincenzo Ciancia]

Christofer C. Bell ha scritto:

> There's nothing wrong going on here.  This was a simple case of user
> error.  The user installed software (albeit under a different release)
> that was not compatible with the current release.  The system was
> configured to use software installed in /usr/local prior to being
> upgraded, and continued to do so after being upgraded.  That this
> software was incompatible with the newly installed operating system is
> not the fault of the operating system.

Not to be picky, but the libz that I had in my system actuall was
compatible with the release I was using, hence I did never notice a
problem. Is the _new_ release which is not compatible, where is my error
then? If I can't know in advance what libraries will break the new
system, I have to remove the whole /usr/local before upgrading, this can
be done harmlessly by the system upgrader.

If the user has to foresee any problem with non-distribution packages or
programs, why does ubuntu modify /etc/apt/sources.list? Shouldn't it
apply the same principle, and just leave it untouched? If third party
repositories break the system upgrade, it's just an user error.

> 
> ie; There is nothing to be learned by over analyzing this issue other
> than a valuable life lesson on the part of the system administrator.
> 

In my opinion, there is to learn that upgrades can be broken by various
reasons, and not only by third party repositories. But ubuntu developers
already know this very well, since they develop an upgrade program
separately for each release.

In the very end, I am not a system administrator, but just a desktop
user, and being taught life lessons by my personal computer is the last
thing I expect. The fact that I have long experience with linux does not
make me a system administrator, however it gives me enough knowledge to
be sure that, if I where to write an upgrade program, or any other
system tool which can seriously damage a running system, I would *NOT*
keep /usr/local/lib in the library path.

I expected anything out of this thread, but people defending the idea
that keeping /usr/local/lib in the library path during system upgrades
is a good idea. I can accept to have problems *after* the upgrade, but
not to be left with an unusable system just because I had stuff in
/usr/local and that's my fault.

Vincenzo