Unable to update containers from deployed machine

[danbst]

I've deployed a virtualbox machine with NixOps. The config contains a declarative container specification inside. After deploy container is started and works OK.

But when I change configuration and redeploy my virtualbox machine, the container isn't updated (NixOS/nixpkgs#3021 (comment)). So I nixops ssh to machine and try to nixos-container update container manually. But that doesn't work:

# nixos-container update pvk
warning: Nix search path entry ‘/var/lib/containers/pvk/etc/nixos/configuration.nix’ does not exist, ignoring
error: file ‘nixpkgs/nixos’ was not found in the Nix search path (add it using $NIX_PATH or -I)
/run/current-system/sw/bin/nixos-container: failed to build container configuration

Stop and then start for container do the update, but I don't want stopping, I want nixos-rebuild switch-like behavior.

If this is desired behavior, then this should be mentioned in docs.

[danbst]

I found out, that systemctl reload container@.... does the trick in general, so this isn't a NixOps issue.