[CentOS] re-install package

Thu Apr 16 07:10:27 UTC 2009
D Tucny <d at tucny.com>

2009/4/16 John Thomas <gmane-2006-04-16 at jt-socal.com>

> Scott Silva wrote:
> > And the right repositories have to be online!
>
> Finally, a successful commercial repository.
>

It's not without it's problems though, especially when using yum... Blindly
playing with this repository can be bad for your system's health, plenty of
care and attention is required...

The packages require quite a bit of ongoing maintence once installed and not
all versions are stable... The packages don't tend to carry much
documentation, the reported requirements are not always accurate and the
package clean up routines are never complete...

yum update girlfriend doesn't typically work too well if a prior version is
already installed, newer versions get installed then a cleanup happens
afterwards, race conditions exist where the previous version can do lots of
bad things to your system while both versions are effectively installed at
the same time... a yum remove girlfriend before a fresh yum install
girlfriend is recommended... Care should still be taken as yum will attempt
to honour the package dependancies and other packages such as pet, house and
car could be removed when trying to remove girlfriend, especially if any of
those were installed after girlfriend and more so if it was requires of the
girlfriend package that triggered their installation... Typically there are
significant system reconfigurations required to support each new version...
yum reinstall doesn't always work too well with girlfriend, the package does
tend to leave quite a bit of state information in place, even after
uninstall, which, if this is the cause of the problems, won't be fixed by a
reinstall...

An upgrade of girlfriend to wife exists, it's not cheap though and
potentially can require some major system reconfiguration to support... yum
can't really handle this, often getting confused between the option of
upgrading to wife or updating to a later release of girlfriend... The
upgrade to wife can be forced in certain situations such as if any child
packages have been accidentally installed, such as by automatic overnight
updates...

With wife installed, yum will let you install additional versions of
girlfriend, but, this is not a recommended configuration as there are some
very serious interoperability issues, especially if an installation of
girlfriend pulls in a child update... In that situation, yum would try to
upgrade girlfriend to wife, but, as you can't, in a standard configuration,
have multiple instances of wife and newer versions of wife obsolete older
versions, the old version would need to be removed, the massive number of
unresolvable dependancies involved in the that would cause yum to crash...
The only solution is to use rpm with varying force and nodeps options to
attempt to get your system functional again, though even then, bits of old
packages will still be lying around consuming resources, especially if child
packages exist...

So, while the packages can work, there is quite a bit of work involved in
fully integrating them and maintaining them... yum can be used, but, it's
probably best to exclude them in yum.conf and manually install and update
the packages where you find necessary, taking great care in avoiding
conflicts and managing dependancies... The extra care taken in doing it
manually can really pay off in long term system stability...
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