Re: How to install guix system from existing linux with guix package manager?

[kiasoc5]

Hi Giovanni,

May 27, 2022, 10:06 AM, "Giovanni Biscuolo" <g@xelera.eu 
mailto:g@xelera.eu?to=%22Giovanni%20Biscuolo%22%20%3Cg%40xelera.eu%3E > wrote:

> IMHO what you are trying to do is an interesting path to... ascension

Ascension, that's a great way to put it!

> For my desktop and laptop I'm still using Guix on top of a foreign
> distro (Debian) because... I'm conservative :-D, so I'd very much like
> to have a way to try to slowly switch to Guix System with the "safety
> net" to be able to boot my current system if I'm in trouble; this way
> also I can spare some cash avoiding to buy a new dedicated machine for
> this experiments.
> 

I plan to try it out in a VM first. The new Arch installer sets up btrfs 
subvolumes automatically so it will be good for testing.

> I never tried this, but beware that the UID and GID of user(s) in
> your new Guix System sould be the very same of the arch system to be
> able to access homes, /including/ Guix profiles of users (stored in
> /home/$USER...)

Yes, I believe most Linuxes set the first created user to a UID and GID of 
1000, so hopefully this is not an issue.

> Important: if you want to be able to share the store between the two
> systems you should also share the /status/ of Guix, stored in
> LOCALSTATEDIR/guix/ (usually /var/guix), since it contains a lot of
> useful data and AFAIU it must be kept in sync between the foreign distro
> and the Guix System [1]. This is the most critical part about being
> able to share Guix between two different host operating systems.

Should I make /var/guix a subvolume as well?

ALso the only directory in /gnu is /gnu/store right? So I could just have an 
@gnu subvolume mounted on /gnu instead of a @gnu-store subvolume mounted on 
/gnu/store?

> Last but not least, once you have installed Guix System you have to
> decide what manages your GRUB configuraton: Guix System or arch, you
> cannot share the grub config between the two; Guix System have a
> stateless GRUB config (and it' good and fair) so I suggest you to use it
> for GRUB configuration, but if you decide to keep using arch this is a
> good tip: https://yhetil.org/guix/20181031125428.GA814@doom/

Thanks for the tip. What if I install another bootloader on Arch like systemd 
boot? Then there will not be a bootloader conflict and I can select one with 
efibootmgr.

May 28, 2022, 10:51 AM, "Giovanni Biscuolo" <g@xelera.eu 
mailto:g@xelera.eu?to=%22Giovanni%20Biscuolo%22%20%3Cg%40xelera.eu%3E > wrote:

> Actually I'm using a shared store AND "LOCALSTATEDIR/guix/" (usually
> /var/guix) between my host OS and all my LXC containers, it's something
> I learned by adapting Ludo' and Ricardo notes on installing Guix on a
> cluster; please see this message (it was Feb 2019, I forgot I wrote
> that) for details and pointers to the relevant documentation:
> 
> https://yhetil.org/guix/87h8d8dl6d.fsf@roquette.mug.biscuolo.net/
> 
> In your case the "store and state sharing" systems are not running and
> at the same time like on a cluster, but from a systemistic point of view
> it's (almost) the same thing some of us are already doing in their
> setup.

Interesting, this does have some parallels.

> As a side note, you could also consider to switch to Guix System and
> keep your foreign distro running as an LXC container sharing store and
> state with the host, but you have to be familiar with LXC tooling [1]
> AND know how to "convert" a "physical" machine to an LXC container [2],
> giving the guests acces to the host GPU [3] for graphical applications
> or using remote dektop applications like SPICE or VNC... it's a little
> bit complex but pure fun!

Would an LXC approach require two graphics cards? I only have an integrated GPU.

Thanks,
kiasoc5