[Nix-dev] Is $NIX_OTHER_STORES still supported?

[Eelco Dolstra]

Hi Peter,

On 31/05/15 11:33, Peter Simons wrote:

> I've been trying to make my NixOS re-use another machine's store, but
> I've had no success. I've mounted the other machine's file system as
> follows:
> 
>   # mkdir /run/nix/remote-stores/other
>   # sshfs -o allow_root other:/ /run/nix/remote-stores/other
> 
> The other's /nix directory is visible:
> 
>   # ls -ld $NIX_OTHER_STORES
>   drwxr-xr-x 1 root root 4096 Mar 27  2014 /run/nix/remote-stores/other/nix
> 
> However, my nix-env operations never seem to access that store, even
> though I know for sure that it contains the derivations I'm installing.
> 
> Is there anything else I have to do to activate this feature?

It's not enabled by default. You need to set NIX_SUBSTITUTERS to include
copy-from-other-stores.pl.

Check out the NixOS installer, which uses it to ensure that binaries are copied
from the installation CD:

https://github.com/NixOS/nixos/blob/master/modules/installer/tools/nixos-install.sh

However, NIX_OTHER_STORES might be removed at some point because it doesn't work
well anymore for access to remote stores since Nix started used SQLite.

-- 
Eelco Dolstra | LogicBlox, Inc. | http://nixos.org/~eelco/