Subject: Re: [bug#65335] [PATCH 0/4] Allow mounting root on tmpfs for impersistence

From: Nicolas Graves <[email-masked]>
Date: Mon, 21 Aug 2023 00:15:22 +0200

On 2023-08-16 11:24, Nicolas Graves via Guix-patches via wrote:

> This patch series allows the root to be mounted on tmpfs, and ensures directories that are needed are present. Once the persisting directories needed are configured (with btrfs for instance), one can mount root on tmpfs. These persisting directories should be at least /var/log (not needed, but safety requirement), /var/lib, /var/guix, but they are application-dependent (if using NetworkManager, /etc/NetworkManager; if guix offloading daemon is present, /etc/guix; the same goes for Docker...).
>
> Nicolas Graves (4):
>   file-systems: canonicalize-device-name: Ignore the "none" case.
>   gnu: services: activation-script: Ensure /var/run existence.
>   gnu: build: activate-current-system: Ensure directory existence.
>   gnu: system: bootable-kernel-arguments: Ignore the "none" root case.
>
>  gnu/build/activation.scm   |  1 +
>  gnu/build/file-systems.scm |  8 ++++----
>  gnu/services.scm           |  1 +
>  gnu/system.scm             | 21 ++++++++++++---------
>  4 files changed, 18 insertions(+), 13 deletions(-)
>

A new update with a little addition for the home symlink-manager, in the
same idea of enabling impermanence configurations on guix.

I've experienced a few issues with the home symlink-manager, in the case
where

To explain the use case for this last commit : in the hypothesis in
which we use a dedicated btrfs to save for instance the ~/.ssh or the
~/.local/share directory, when running guix home reconfigure, the
activation script will error before ending with an EBUSY error. This
will make the home reconfiguration fail, while the most sensible action
in this case is to ignore the deletion call and continue, just like when
a configuration directory is not empty.

This is not enough for enabling impermanence home configurations, but it
enables to reconfigure the home with btrfs subvolumes under ~. 

-- 
Best regards,
Nicolas Graves