[Nix-dev] nixos-rebuild without Internet

James Cook james.cook at utoronto.ca
Sun Jun 25 03:20:07 CEST 2017

On 24 June 2017 at 22:52, Maximilian Bosch <maximilian at mbosch.me> wrote:
> Hey guys,
> I'm using a NixOS setup on my developer machine. For WLAN networks I use the
> `networking.wireless` option as it allows me a declarative/reproducible
> setup of the networks I use on a daily basis.
> Unfortunately I'm facing from time to time the following issue: whenever I
> try to add a new network (and no connection is available ATM) I have a
> problem running `nixos-rebuild` as the rebuild usually causes a lot of other
> operations and some of them require a connection to the internet (e.g. for
> [re]downloads).
> However this is quite bad when I need a new network, but the rebuild fails.
> I currently solve it using several tricks, but in the end I'd like to now if
> there's some kind of tool to do a "partial-rebuild" on a NixOS machine
> (although it might break the reproducability as the expressions wouln'dt be
> 100%-deterministic anymore) or if I have to live with this issue.
> Thanks and have a nice Sunday,
> Maximilian

Hi Maximilian,

If you only make a configuration change like reconfiguring a network
interface, I'd expect nixos-rebuild to work without a network.

If you update your nixpkgs version (e.g. nix-channel --update or git
pull or passing --upgrade to nixos-rebuild) that could mean the next
build requires a network connection. Could that be it?

Or is it trying to access the binary cache? If so, there's surely some
way to disable that so it builds everything locally.


More information about the nix-dev mailing list