[Nix-dev] strange nix error

[James Cook]

On 5 April 2014 16:47, Ben Franksen <ben.franksen at online.de> wrote:
> Hi
>
> I have installed nix under ubuntu, using the ubuntu deb package. Then I
> followed the instructions in the nix manual for multi-user installs, i.e.
> created build users & groups and added a nix.conf:
>
> ben at sarun[1]: ~ > sudo dpkg -i nix_1.6.1-1_amd64.deb
> <output elided>
> bben at sarun[1]: ~ > cat nix-setup-build-users.sh
> #!/bin/sh
> addgroup --quiet --gid 40000 nixbld
> for i in 1 2 3 4 5 6 7 8 9; do
>   adduser --quiet --system --disabled-password --no-create-home --
> uid="4000$i" --gecos "Nix build user $i" --ingroup nixbld "nixbld$i"
>   adduser --quiet "nixbld$i" nixbld
> done
> chgrp nixbld /nix/store
> chmod 1775 /nix/store
> ben at sarun[1]: ~ > sudo sh ./nix-setup-build-users.sh
> ben at sarun[1]: ~ > grep nix /etc/{group,passwd}
> /etc/group:nixbld:x:40000:nixbld1,nixbld2,nixbld3,nixbld4,nixbld5,nixbld6,nixbld7,nixbld8,nixbld9
> /etc/passwd:nixbld1:x:40001:40000:Nix build user
> 1,,,:/home/nixbld1:/bin/false
> /etc/passwd:nixbld2:x:40002:40000:Nix build user
> 2,,,:/home/nixbld2:/bin/false
> /etc/passwd:nixbld3:x:40003:40000:Nix build user
> 3,,,:/home/nixbld3:/bin/false
> /etc/passwd:nixbld4:x:40004:40000:Nix build user
> 4,,,:/home/nixbld4:/bin/false
> /etc/passwd:nixbld5:x:40005:40000:Nix build user
> 5,,,:/home/nixbld5:/bin/false
> /etc/passwd:nixbld6:x:40006:40000:Nix build user
> 6,,,:/home/nixbld6:/bin/false
> /etc/passwd:nixbld7:x:40007:40000:Nix build user
> 7,,,:/home/nixbld7:/bin/false
> /etc/passwd:nixbld8:x:40008:40000:Nix build user
> 8,,,:/home/nixbld8:/bin/false
> /etc/passwd:nixbld9:x:40009:40000:Nix build user
> 9,,,:/home/nixbld9:/bin/false
> ben at sarun[1]: ~ > cat /etc/nix/nix.conf
> build-users-group = nixbld
> build-max-jobs = 2
> auto-optimise-store = true
>
>
> Then I do nix-env -i <somepackage> and get
>
> error: setting synchronous mode: unable to open database file
>
> Any idea what went wrong?
>
> Cheers
> Ben
> --
> "Make it so they have to reboot after every typo." -- Scott Adams

I had a similar problem, and fixed it by setting the environment
variable NIX_REMOTE to "daemon" as suggested in the user's guide.

James