[arch-general] Multiple Kernels

[Heiko Baums]

Am Mon, 1 Feb 2010 20:48:14 +0100
schrieb Tom <uebershark at googlemail.com>:

> I don't really get that. I'm no expert in using pacman or writing
> PKGBUILDs, but I can very readily imagine a mechanism that on each
> rolling release update to the kernel, moves the current kernel on the
> users system to say 'kernel-previous', and puts the update in place
> for 'kernel'.
> Add a line to grub to reflect the two kernel-versions (current and
> previous) and handle this with symlinks so that the actual kernel +
> libs and so on can have version names.
> 
> On the other hand, I have never had a kernel-update completely break
> my system, so the question really is, if automation of such
> functionality is needed.
> After all, you really should compile your own kernels, and keep
> backups around just in case you break something there yourself...

I used Gentoo some years before I switched to Arch. Gentoo is also a
rolling release distro. And Gentoo keeps several older versions of
every package in the portage tree, so that you can easily install a
version of your choice and downgrade every package to every version you
want. On Gentoo sometimes this is necessary, but it also makes the
distro more complex. On Arch this wasn't really necessary, yet.

On Gentoo the older kernel version was kept on the system and renamed
to /boot/vmlinuz.old etc. when the kernel was updated.

And neither on Gentoo nor on Arch I had to downgrade the kernel once.
And also on Gentoo I always removed the older kernel version directly
after updating the kernel and before rebooting and I never had a
problem.

So Arch should stay with its policy to only provide the latest version
of a package.

And if you really need to downgrade the kernel or another package just
do it with pacman -U /var/cache/pacman/pkg/<packagename>-<oldversion>.

Greetings,
Heiko