Subject: Re: Apt Question
UTC Time: May 23, 2017 11:54 AM
From: wooledg@eeg.ccf.org
> If he
> is already running a sid linux kernel and some other core packages by
> switching to jessie he will be stuck with those packages almost indefinitely,
He's not running jessie, nor could he "switch to jessie" if he wanted
to. Once you've installed a single binary package from post-jessie,
there is no going back.
Doesn't it relate to how essential the package is for the system to continue running? With kernels beeing completely different packages it only matters which one you use to boot from. I don't think you can completely remove systemd and reinstall it. But something non essential that would only run when you call it you can completely remove and reinstall from jessie. But I agree that once you have moved up a notch there are too many packages to replace without crashing. I've never tried it but synaptics says you can select and force from which repository to keep. I don't know whether it is possible to revert this way, I'll be trying it soon if nobody says it doesn't work.
Likewise, once you have installed a single binary package from
post-stretch (e.g. sid), there is no going back.
I don't think this is completely true and always. I remember having something that was flaky in testing and switched repositories, installed one from unstable I think, it had the same problem, I didn't updgrade anything else, completely removed, readjusted sources.list and reinstalled the current package. But it was a package the system could live without. Maybe it just happened that its dependencies in testing and unstable were the same.