Re: Fwd: yum rollback !!

On Wed, 2008-04-02 at 06:39 +1100, David Timms wrote:
> Tim Lauridsen wrote:
> > The mayor problem with roleback is that you can't reverse the changes 
> > done by scriptlets in RPM, so it is not posible to do downgrade in a 
> > safeway.
> > 
> > EX.
> > 
> > rpm -ivh foo
> > rpm -e foo
> > 
> > these commands add a package and remove it again.
> > the state of the system might not be the same before and after these 
> > commands, so a safe rollback is not possible.
> 
> Further to what Alastair says later in the thread:
> what if a yum plugin stored the information about what a script file 
> actions looked like before/after the rpm install modified a file ?
> 
> yum install foo
> [foo renamed /etc/foo.cfg to /etc/foo.cfg.rpmold: versioned at ...]
> [foo created /etc/foo.cfg: versioned at /var/cache/rollback/...]
> 
> I guess that is a bit simplified; it's not just config files that can 
> get modified in scriptlets. Perhaps you could version the /etc/ folder 
> and commit any change after each yum transaction ?

it's not just /etc

think about updates like:
mysql4 -> mysql5

you have to roll back the db versions
and NOT roll back the data.

there is deep doom down these lines.

-sv