The theory of upgrading from 14.04 to 15.04 using /etc/apt/sources.list

[Oliver Grawert]

hi,
Am Montag, den 10.08.2015, 10:35 -0500 schrieb William Scott Lockwood
III:
> On Mon, Aug 10, 2015 at 10:32 AM, Colin Law <clanlaw at gmail.com> wrote:
> >> The point is that he said he might want to do it that way. I don't
> >> judge as to why someone wants to do something one way vs another. It
> >> is possible. I'd rather give accurate information than tell someone
> >> something can't be done when in fact it is possible.
> >
> > I did not suggest it can't be done, I just asked why he did not want
> > to do it the recommended way.
> 
> 
> Actually, your exact words were:
> > Even if it appears to work in a VM that is no guarantee that it will
> > work on another machine with different packages installed.
> 
> That's the part I was calling FUD. Not the rest of it.
> 
and there is no FUD in these words at all ...

there are upgrade methods that get tested a many thousand times before a
release ... as it happens these upgrade methods also take care for data
migration to new versions of apps shipped in the images, for abandoned
software and config migration...

...and then there are upgrade methods that do not get tested at all and
will appear work by sheer luck, like mangling your sources list and
blindly upgrading. nobody can tell if the configs are still proper
afterwards, if you accidentially rip giant security holes by skipping
the migration etc ... 

there are a few hundred people doing upgrade testing every release and
they all only test one path (and even there they find 100s of hidden
bugs)... calling a warning about a completely untested upgrade path FUD
is pretty ignorant towards the voluntary work of all these people
IMHO ... it can break (and it will *defninitely* get you a different
result from doing the two step official upgrade, feel free to check the
update-manager source). 

so i think a warning is well put if someone asks about leaving the
default paths ...

ciao
	oli