[Nix-dev] configuration management question

[Marc Weber]

Excerpts from germsteel's message of Sat Jul 31 06:44:48 +0200 2010:
> 
> Here's my dream: drive on machine fails, install os on new drive, feed it
> some "magical" config file and
> boom everything is working like before but even better.  Am I dreaming or
> could nixos do this?

Get a backup system - or use raid. You don' need Nix for this.

How to realize your dream using Nix:
====================================

Make nix backup your system (user state. eg $HOME/) and database states
and such.
Then store the configuration.nix file - if you want to restore you
system not having updated it for month - export your store as well -
because some sources are likely to "vanish"..

Then modify the live cds so tha they
- boot (already done)
- fetch your configuration file [easy]
- fetch the revision of nixos/nixpkgs you used that time [easy]
- start an automatic installation [easy]
- issue reboot [easy]

> the new system.  I am NOT talking about restoring a backup or image.  I want
> a NEW OS and software (samba for example) with my old settings -- is this
> even possible?
Mmmh somewhat, yes. I'm not sure about the status of smbpasswd. Maybe
you have to reconfigure passwords.

These daemons are already supported by NixOS. completeness of
implementation varies: (Scroll to bottom. You'll find samba there)
http://hydra.nixos.org/job/nixos/trunk/manual/latest/download/1/nixos/manual.html
                                              ^^^^ bookmark this /latest/ link.

Marc Weber