Guix/GNU/Linux multi distro + GuixSD multi-site scenario

Guix/GNU/Linux multi distro + GuixSD multi-site scenario

[myglc2]

These are questions about a Guix user scenario I am contemplating.

Situation:

- I have installed Guix/Debian and GuixSD on a couple home servers
  (behind a typical broadband router).

- I am running Guix from a git checkout to which I have applied personal
  patches.

- TODO I talk my friendly sysadmins at a couple organizations into
  installing Guix on /GNU/Linux distros, say ubuntu and centos.

It seems obvious that Guix supports this scenario. But it is not so
obvious what the best way to 'instantiate' it is ;)

So I have a few questions:

1) What is a practical way to get the same identical versions of my
   customized guix packages running on all the machines?

2) What is a good setup that allows me to make and coordinate changes in
   my package manifest, package recipes, and Guix version anywhere?

3) I may want to source substitutes from my home servers. Any words of
   wisdom?

You can assume that I know how to tunnel between the sites, use git,
manage remote git repos, and have a reasonable user-level knowledge of
Guix and GuixSD.

TIA - George

Re: Guix/GNU/Linux multi distro + GuixSD multi-site scenario

[Christopher Allan Webber]

myglc2 writes:

> These are questions about a Guix user scenario I am contemplating.
>
> Situation:
>
> - I have installed Guix/Debian and GuixSD on a couple home servers
>   (behind a typical broadband router).
>
> - I am running Guix from a git checkout to which I have applied personal
>   patches.
>
> - TODO I talk my friendly sysadmins at a couple organizations into
>   installing Guix on /GNU/Linux distros, say ubuntu and centos.
>
> It seems obvious that Guix supports this scenario. But it is not so
> obvious what the best way to 'instantiate' it is ;)
>
> So I have a few questions:
>
> 1) What is a practical way to get the same identical versions of my
>    customized guix packages running on all the machines?

Running all machines, I dunno.  I do dual-boot Debian and GuixSD with
them sharing the same user profile and store.  On Debian, I bind-mount
some directories from GuixSD's root partition.  From /etc/fstab:

UUID=d9cc11f0-e548-4526-a541-4f631a10b73c /mnt/guix/      ext4    defaults        0       2
/mnt/guix/var/guix    /var/guix           none            defaults,bind           0       0
/mnt/guix/gnu    /gnu                     none            defaults,bind           0       0

Then /home/ is shared (and luks encrypted) on both distros.  It works
fine.

If you want to do "same profile and store across all things" Ricardo
Wurmus does some wild things using NFS.

Re: Guix/GNU/Linux multi distro + GuixSD multi-site scenario

[myglc2]

Christopher Allan Webber <cwebber@dustycloud.org> writes:
[...]
>
> Running all machines, I dunno.  I do dual-boot Debian and GuixSD with
> them sharing the same user profile and store.

Dual boot. Now that is cool!

> On Debian, I bind-mount
> some directories from GuixSD's root partition.  From /etc/fstab:
>
> UUID=d9cc11f0-e548-4526-a541-4f631a10b73c /mnt/guix/      ext4    defaults        0       2
> /mnt/guix/var/guix    /var/guix           none            defaults,bind           0       0
> /mnt/guix/gnu    /gnu                     none            defaults,bind           0       0
>
> Then /home/ is shared (and luks encrypted) on both distros.  It works
> fine.

I was thinking of a substitutes approach and hadn't thought of sharing
guix and /gnu. I could do that on my home servers.

> If you want to do "same profile and store across all things" Ricardo
> Wurmus does some wild things using NFS.

If he doesn't comment maybe I will contact him.

Thank you for the comments. - George

Re: Guix/GNU/Linux multi distro + GuixSD multi-site scenario

[Christopher Allan Webber]

myglc2 writes:

> Christopher Allan Webber <cwebber@dustycloud.org> writes:
> [...]
>>
>> Running all machines, I dunno.  I do dual-boot Debian and GuixSD with
>> them sharing the same user profile and store.
>
> Dual boot. Now that is cool!

Dual booting allowed me to switch to GuixSD a lot more feasibly than I
could have otherwise.  I installed it on this laptop right before a 3
month trip.  Dual booting meant that when something wasn't in GuixSD
yet, no problem, I could switch to Debian for a bit.  Then I could work
on packages at my leisure to switch over.

The trick was realizing that the grub that Guix generates wasn't the one
I should boot into... I needed to have Guix and Debian generate their
own grub files on their own partitions, and then have a /boot/ grub
which was reeeeaally small and simply had menu options to import those
other grub files.

Re: Guix/GNU/Linux multi distro + GuixSD multi-site scenario

[myglc2]

Christopher Allan Webber <cwebber@dustycloud.org> writes:

> myglc2 writes:
>
>> Christopher Allan Webber <cwebber@dustycloud.org> writes:
>> [...]
>>>
>>> Running all machines, I dunno.  I do dual-boot Debian and GuixSD with
>>> them sharing the same user profile and store.
>>
>> Dual boot. Now that is cool!
>
> Dual booting allowed me to switch to GuixSD a lot more feasibly than I
> could have otherwise.  I installed it on this laptop right before a 3
> month trip.  Dual booting meant that when something wasn't in GuixSD
> yet, no problem, I could switch to Debian for a bit.  Then I could work
> on packages at my leisure to switch over.
>
> The trick was realizing that the grub that Guix generates wasn't the one
> I should boot into... I needed to have Guix and Debian generate their
> own grub files on their own partitions, and then have a /boot/ grub
> which was reeeeaally small and simply had menu options to import those
> other grub files.

Neat!. Normally grub would be installed like this...

  (bootloader (grub-configuration (device "/dev/sda")))
  (file-systems (cons (file-system
                        (device "/dev/sda1")
                        (title 'device)
                        (mount-point "/")
                        (type "ext4"))
                      %base-file-systems))

But it sounds like you are installing a custom /boot/grub in
/dev/sda. So where is the GuixSD Grub and /?

I am very interested in your GuixSD vs Guix/Debian experience.  I have
run GuixSD and Guix/Debian over the last two months on my headless
servers. Initially I installed GuixSD because I wanted the "full monty."
Then I put Guix/Debian because I wanted to understand the difference
between GuixSD and Guix/GNU/Linux.

Finally I caught on to the Guix strategy of installing as
little-as-possible in the system profile (using Debian package manager
or Guix System Configuration). If one follows this approach, it seems to
me that there is very little difference between GuixSD and Guix/Debian,
except that Debian has better hardware support and so is more likely to
install w/o issues.

Do you see it that way or am I missing something?

Re: Guix/GNU/Linux multi distro + GuixSD multi-site scenario

[Alex Kost]

myglc2 (2016-03-27 20:18 +0300) wrote:

> Christopher Allan Webber <cwebber@dustycloud.org> writes:
>
>> myglc2 writes:
>>
>>> Christopher Allan Webber <cwebber@dustycloud.org> writes:
>>> [...]
>>>>
>>>> Running all machines, I dunno.  I do dual-boot Debian and GuixSD with
>>>> them sharing the same user profile and store.
>>>
>>> Dual boot. Now that is cool!
>>
>> Dual booting allowed me to switch to GuixSD a lot more feasibly than I
>> could have otherwise.  I installed it on this laptop right before a 3
>> month trip.  Dual booting meant that when something wasn't in GuixSD
>> yet, no problem, I could switch to Debian for a bit.  Then I could work
>> on packages at my leisure to switch over.
>>
>> The trick was realizing that the grub that Guix generates wasn't the one
>> I should boot into... I needed to have Guix and Debian generate their
>> own grub files on their own partitions, and then have a /boot/ grub
>> which was reeeeaally small and simply had menu options to import those
>> other grub files.
>
> Neat!. Normally grub would be installed like this...
>
>   (bootloader (grub-configuration (device "/dev/sda")))
>   (file-systems (cons (file-system
>                         (device "/dev/sda1")
>                         (title 'device)
>                         (mount-point "/")
>                         (type "ext4"))
>                       %base-file-systems))
>
> But it sounds like you are installing a custom /boot/grub in
> /dev/sda. So where is the GuixSD Grub and /?

Hi, I also use double boot (GuixSD and ArchLinux).  I do it like this:
at first I never let GuixSD to reinstall grub by using --no-grub option
("guix system reconfigure --no-grub ...").  Instead I installed grub
manually (into a separate "boot" partition) and I use my own "grub.cfg",
which has an entry for the latest GuixSD system.  This entry may look
like this:

menuentry 'GuixSD' {
    search --no-floppy --label --set guix
    linux  /var/guix/profiles/system/kernel/bzImage --root=guix --system=/var/guix/profiles/system --load=/var/guix/profiles/system/boot
    initrd /var/guix/profiles/system/initrd
}

My grub config¹ also has entries for a previous system generation (I can
boot any generation by editing a number in a grub boot menu) and for a
particular system (sometimes I do "guix system build …" and put the
result directory of this "testing" system to my grub.cfg).

¹ https://github.com/alezost/config/blob/master/etc/grub.cfg

-- 
Alex

Re: Guix/GNU/Linux multi distro + GuixSD multi-site scenario

[myglc2]

Alex Kost <alezost@gmail.com> writes:
[...]
>
> Hi, I also use double boot (GuixSD and ArchLinux).  I do it like this:
> at first I never let GuixSD to reinstall grub by using --no-grub option
> ("guix system reconfigure --no-grub ...").  Instead I installed grub
> manually (into a separate "boot" partition) and I use my own "grub.cfg",
> which has an entry for the latest GuixSD system.  This entry may look
> like this:
>
> menuentry 'GuixSD' {
>     search --no-floppy --label --set guix
>     linux  /var/guix/profiles/system/kernel/bzImage --root=guix --system=/var/guix/profiles/system --load=/var/guix/profiles/system/boot
>     initrd /var/guix/profiles/system/initrd
> }
>
> My grub config¹ also has entries for a previous system generation (I can
> boot any generation by editing a number in a grub boot menu) and for a
> particular system (sometimes I do "guix system build …" and put the
> result directory of this "testing" system to my grub.cfg).
>
> ¹ https://github.com/alezost/config/blob/master/etc/grub.cfg

Nice! Grub is kind of a netherworld for me. It is great to see a
tangible example like this. Thanks! - George

Re: Guix/GNU/Linux multi distro + GuixSD multi-site scenario

[Chris Marusich]

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Alex Kost <alezost@gmail.com> writes:

> Hi, I also use double boot (GuixSD and ArchLinux).  I do it like this:
> at first I never let GuixSD to reinstall grub by using --no-grub option
> ("guix system reconfigure --no-grub ...").  Instead I installed grub
> manually (into a separate "boot" partition) and I use my own "grub.cfg",
> which has an entry for the latest GuixSD system.  This entry may look
> like this:
>
> menuentry 'GuixSD' {
>     search --no-floppy --label --set guix
>     linux  /var/guix/profiles/system/kernel/bzImage --root=guix --system=/var/guix/profiles/system --load=/var/guix/profiles/system/boot
>     initrd /var/guix/profiles/system/initrd
> }
>
> My grub config¹ also has entries for a previous system generation (I can
> boot any generation by editing a number in a grub boot menu) and for a
> particular system (sometimes I do "guix system build …" and put the
> result directory of this "testing" system to my grub.cfg).
>
> ¹ https://github.com/alezost/config/blob/master/etc/grub.cfg

If you take the path from guix system build and manually insert it into
your grub.cfg file, do you have any guarantee that the next guix gc
won't remove your system files?

-- 
Chris

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Re: Guix/GNU/Linux multi distro + GuixSD multi-site scenario

[Alex Kost]

Chris Marusich (2016-03-28 17:32 +0300) wrote:

> Alex Kost <alezost@gmail.com> writes:
>
>> Hi, I also use double boot (GuixSD and ArchLinux).  I do it like this:
>> at first I never let GuixSD to reinstall grub by using --no-grub option
>> ("guix system reconfigure --no-grub ...").  Instead I installed grub
>> manually (into a separate "boot" partition) and I use my own "grub.cfg",
>> which has an entry for the latest GuixSD system.  This entry may look
>> like this:
>>
>> menuentry 'GuixSD' {
>>     search --no-floppy --label --set guix
>>     linux  /var/guix/profiles/system/kernel/bzImage --root=guix --system=/var/guix/profiles/system --load=/var/guix/profiles/system/boot
>>     initrd /var/guix/profiles/system/initrd
>> }
>>
>> My grub config¹ also has entries for a previous system generation (I can
>> boot any generation by editing a number in a grub boot menu) and for a
>> particular system (sometimes I do "guix system build …" and put the
>> result directory of this "testing" system to my grub.cfg).
>>
>> ¹ https://github.com/alezost/config/blob/master/etc/grub.cfg
>
> If you take the path from guix system build and manually insert it into
> your grub.cfg file, do you have any guarantee that the next guix gc
> won't remove your system files?

That's why if I really need a system, I do a reconfiguring.  I use "guix
system build" just to test a system.  If it's OK, I reconfigure the
system, otherwise I don't need it and I want it to be gc-ed.  Besides, I
do "guix gc" very rarely (once in several months), and before it, I
carefully check what profiles/system generations I want to keep and what
can be removed.

-- 
Alex

Re: Guix/GNU/Linux multi distro + GuixSD multi-site scenario

[Christopher Allan Webber]

Alex Kost writes:

> myglc2 (2016-03-27 20:18 +0300) wrote:
>
>> Christopher Allan Webber <cwebber@dustycloud.org> writes:
>>
>>> myglc2 writes:
>>>
>>>> Christopher Allan Webber <cwebber@dustycloud.org> writes:
>>>> [...]
>>>>>
>>>>> Running all machines, I dunno.  I do dual-boot Debian and GuixSD with
>>>>> them sharing the same user profile and store.
>>>>
>>>> Dual boot. Now that is cool!
>>>
>>> Dual booting allowed me to switch to GuixSD a lot more feasibly than I
>>> could have otherwise.  I installed it on this laptop right before a 3
>>> month trip.  Dual booting meant that when something wasn't in GuixSD
>>> yet, no problem, I could switch to Debian for a bit.  Then I could work
>>> on packages at my leisure to switch over.
>>>
>>> The trick was realizing that the grub that Guix generates wasn't the one
>>> I should boot into... I needed to have Guix and Debian generate their
>>> own grub files on their own partitions, and then have a /boot/ grub
>>> which was reeeeaally small and simply had menu options to import those
>>> other grub files.
>>
>> Neat!. Normally grub would be installed like this...
>>
>>   (bootloader (grub-configuration (device "/dev/sda")))
>>   (file-systems (cons (file-system
>>                         (device "/dev/sda1")
>>                         (title 'device)
>>                         (mount-point "/")
>>                         (type "ext4"))
>>                       %base-file-systems))
>>
>> But it sounds like you are installing a custom /boot/grub in
>> /dev/sda. So where is the GuixSD Grub and /?
>
> Hi, I also use double boot (GuixSD and ArchLinux).  I do it like this:
> at first I never let GuixSD to reinstall grub by using --no-grub option
> ("guix system reconfigure --no-grub ...").  Instead I installed grub
> manually (into a separate "boot" partition) and I use my own "grub.cfg",
> which has an entry for the latest GuixSD system.  This entry may look
> like this:
>
> menuentry 'GuixSD' {
>     search --no-floppy --label --set guix
>     linux  /var/guix/profiles/system/kernel/bzImage --root=guix --system=/var/guix/profiles/system --load=/var/guix/profiles/system/boot
>     initrd /var/guix/profiles/system/initrd
> }
>
> My grub config¹ also has entries for a previous system generation (I can
> boot any generation by editing a number in a grub boot menu) and for a
> particular system (sometimes I do "guix system build …" and put the
> result directory of this "testing" system to my grub.cfg).
>
> ¹ https://github.com/alezost/config/blob/master/etc/grub.cfg

Hm, I think this approach is not quite as nice, IMO.  One downside here
is that by not using the grub that guix generates for you, you can't
simply boot into a prior system revision if something goes long, which
is a huge advantage in GuixSD.

Here's what I do on my grub.cfg (or libreboot_grub.cfg technically):

  set timeout=5
  insmod ahci
  insmod chain
  
  menuentry "Guix" {
    set root=(ahci0,msdos7)
    configfile /boot/grub/grub.cfg
    unset superusers  # probably not needed
  }
  
  menuentry "Debian" {
    set root=(ahci0,msdos6)
    configfile /boot/grub/grub.cfg
    unset superusers  # probably not needed
  }

Re: Guix/GNU/Linux multi distro + GuixSD multi-site scenario

[Alex Kost]

Christopher Allan Webber (2016-03-28 19:39 +0300) wrote:

> Alex Kost writes:
[...]
>> Hi, I also use double boot (GuixSD and ArchLinux).  I do it like this:
>> at first I never let GuixSD to reinstall grub by using --no-grub option
>> ("guix system reconfigure --no-grub ...").  Instead I installed grub
>> manually (into a separate "boot" partition) and I use my own "grub.cfg",
>> which has an entry for the latest GuixSD system.  This entry may look
>> like this:
>>
>> menuentry 'GuixSD' {
>>     search --no-floppy --label --set guix
>>     linux  /var/guix/profiles/system/kernel/bzImage --root=guix --system=/var/guix/profiles/system --load=/var/guix/profiles/system/boot
>>     initrd /var/guix/profiles/system/initrd
>> }
>>
>> My grub config¹ also has entries for a previous system generation (I can
>> boot any generation by editing a number in a grub boot menu) and for a
>> particular system (sometimes I do "guix system build …" and put the
>> result directory of this "testing" system to my grub.cfg).
>>
>> ¹ https://github.com/alezost/config/blob/master/etc/grub.cfg
>
> Hm, I think this approach is not quite as nice, IMO.

Yeah, I think it is not suitable for most people, but it is very nice
for me :-)

> One downside here
> is that by not using the grub that guix generates for you, you can't
> simply boot into a prior system revision if something goes long, which
> is a huge advantage in GuixSD.

As I wrote I can boot into any prior system simply by editing a generation
number in the grub menu.

> Here's what I do on my grub.cfg (or libreboot_grub.cfg technically):
>
>   set timeout=5
>   insmod ahci
>   insmod chain
>
>   menuentry "Guix" {
>     set root=(ahci0,msdos7)
>     configfile /boot/grub/grub.cfg
>     unset superusers  # probably not needed
>   }
>
>   menuentry "Debian" {
>     set root=(ahci0,msdos6)
>     configfile /boot/grub/grub.cfg
>     unset superusers  # probably not needed
>   }

Thanks for sharing!  I didn't think about using "configfile" before.

-- 
Alex

Re: Guix/GNU/Linux multi distro + GuixSD multi-site scenario

[Ludovic Courtès]

Alex Kost <alezost@gmail.com> skribis:

> Christopher Allan Webber (2016-03-28 19:39 +0300) wrote:
>
>> Alex Kost writes:
> [...]
>>> Hi, I also use double boot (GuixSD and ArchLinux).  I do it like this:
>>> at first I never let GuixSD to reinstall grub by using --no-grub option
>>> ("guix system reconfigure --no-grub ...").  Instead I installed grub
>>> manually (into a separate "boot" partition) and I use my own "grub.cfg",
>>> which has an entry for the latest GuixSD system.  This entry may look
>>> like this:
>>>
>>> menuentry 'GuixSD' {
>>>     search --no-floppy --label --set guix
>>>     linux  /var/guix/profiles/system/kernel/bzImage --root=guix --system=/var/guix/profiles/system --load=/var/guix/profiles/system/boot
>>>     initrd /var/guix/profiles/system/initrd
>>> }
>>>
>>> My grub config¹ also has entries for a previous system generation (I can
>>> boot any generation by editing a number in a grub boot menu) and for a
>>> particular system (sometimes I do "guix system build …" and put the
>>> result directory of this "testing" system to my grub.cfg).
>>>
>>> ¹ https://github.com/alezost/config/blob/master/etc/grub.cfg
>>
>> Hm, I think this approach is not quite as nice, IMO.
>
> Yeah, I think it is not suitable for most people, but it is very nice
> for me :-)

It would be interesting to see how we can better support this use case.

I know of at least one potential blocker, which is
<http://bugs.gnu.org/20067>, but probably there are other issues.

Ludo’.