Re: Backport Questions

[Steve Block <scblock@ev-15.com>]

On Wed, Feb 08, 2006 at 09:01:23PM -0800, Marc Shapiro wrote:
> Having seen a number of questions lately responded to by directing the 
> OP to backports, I decided to look into it, myself.  I added backports 
> to my sources.list, did an update and dist-upgrade.  I said 'no' to the 
> actual update so that I could look it over before committing myself to 
> it.  From what I can see, I will probably just remove backports from my 
> sources.list.
>
> From apt-get -u dist-upgrade:
>
> 94 upgraded, 59 newly installed, 8 to remove and 2 not upgraded
>
> The packages to be deleted are:
>
> mysql-client-4.1 mysql-common-4.1 mysql-server-4.1 openoffice.org-bin 
> openoffice.org-debian-files openoffice.org-debian-menus 
> openoffice.org-help-en openoffice.org-l10n-en
>
> Now, I don't care about deleted packages as long as the equivalent is 
> being brought in with other packages, however, I only see 2 mysql 
> packages being installed:
>
> mysql-client-5.0 mysql-common
>
> neither of which provides mysql-server.
>
> Also, the only openoffice files being added are:
>
> openoffice.org-common openoffice.org-core openoffice.org-java-common 
> openoffice.org-l10n-en-us
>
> Of these files:
>
> oo.o-common replaces oo.o-debian-files
> oo.o-core replace oo.o-bin
> oo.o-l10n-en-us replaces oo.o-l10n-en
> oo.o-common-java is new
>
> While the help for 1.1.3 is removed, no help is installed for 2.0
>
> Nothing replaces, or conflicts with openoffice.org-debian-files (that I 
> can see), yet it is being removed.  I'm not surprised that it is not 
> mentioned (in apt-cache show) for any of the packages to be installed, 
> since it was from the package that I dl'd directly from 
> www.openoffice.org that I used to install v 2.0 previously.  IOW it is 
> not from a Debian package, at all.
>
> So, as near as I can tell, doing this dist-upgrade whould leave me 
> without a mysql server, will remove my help for oo.o 1.1 while not 
> providing any for oo.o 2.0 and will break the version 2.0 of oo.o that I 
> currently have installed.
>
> Is this correct, or am I missing something here?

The idea of the backports is not that you use them as a regular package 
repository for keeping your system up to date, but that you bring in 
certain packages that you know you want that aren't in stable. Say you 
are working on a web server and the new content system needs php5. You 
can use the backports packages to migrate (carefully) to php5. I would 
not recommend using it as a generic upgrade system.

The mysql issues you saw were because backports provides mysql-common in 
the 5.0 range, which replaces the 4.1. This requires removing all the 
4.1 mysql packages since they depend on that, but won't cause the 5.0 
mysql packages to automatically be installed.

My recommendation is to keep backports in your sources.list file, but 
add the following to /etc/apt/preferences:

Package: *
Pin: release a=sarge-backports
Pin-Priority: 200

This will keep all the packages in the backports repository at a lower 
priority (200) than the main sarge repositories (500). After that you 
can carefully install whichever backported packages you want to use. 
Sometimes that may involve manually tracking down issues. For example 
to upgrade mysql to 5.0 you now need to override the package priority on 
mysql-common to install the 5.0 version or the other mysql 5 packages 
will be broken. Using aptitude in curses mode makes this pretty easy.

Once again I would not recommend blinding pullingin packages from 
backports, and certainly not trying to dist-upgrade from it.

--
Steve Block
http://ev-15.com/
http://steveblock.com/
scblock@ev-15.com