[Nix-dev] LVM2 support in nixos systemd

[James Cook]

On 20 September 2013 03:05, Lluís Batlle i Rossell <viric at viric.name> wrote:
> Hello,
>
> I noticed that systemd didn't know how to mount (by-label) my lvm raid1. I had a
> lvm raid1 setup before, but it was mounted at stage1 just fine, with the proper
> dozen of modules in initrd.
>
> The nixos systemd didn't have any units distributed with lvm2. I pushed changes
> to make a new systemd derivation in nixpkgs, under the name "systemd_with_lvm2".
> You can use them in nixos, by using:
>
>   systemd.package = pkgs.systemd_with_lvm2;
>   systemd.packages = [ pkgs.lvm2 ];
>
> This made my systemd mount fine the lvm2 raid1 lv. Nevertheless, there is still
> a unit that fails to work. All ends up working, it boots well, and all mounted,
> though.
>
> I've no idea why it fails, and its consequences. Here is what 'status' tells me.
> If anyone knows anything about it, feel free to comment:
>
> --------------------------
> lvm2-activation-net.service - Activation of LVM2 logical volumes
>    Loaded: loaded (/etc/lvm/lvm.conf)
>    Active: failed (Result: exit-code) since dv 2013-09-20 11:42:52 CEST; 19min ago
>      Docs: man:lvm(8)
>            man:vgchange(8)
>   Process: 1441 ExecStart=/nix/store/q1i64p99bvr6jh67k3cfahcighc1psh2-lvm2-2.02.100/sbin/lvm vgchange -aay --sysinit (code=exited, status=5)
>   Process: 1340 ExecStartPre=/nix/store/n9yvgrp6i1fh3jzpbw1cyfvdil0n9j1r-systemd-203/bin/udevadm settle (code=exited, status=0/SUCCESS)
>
> set 20 11:42:52 atom systemd[1]: lvm2-activation-net.service: main process exited, code=exited, status=5/NOTINSSTALLED
> set 20 11:42:52 atom systemd[1]: Failed to start Activation of LVM2 logical volumes.
> set 20 11:42:52 atom systemd[1]: Unit lvm2-activation-net.service entered failed state.
> Warning: Journal has been rotated since unit was started. Log output is incomplete or unavailable.
>
> Warning: Unit file changed on disk, 'systemctl --system daemon-reload' recommended.

I don't know what's going on here, but with my LVM2 setup (not on top
of raid) I never had to tell NixOS I was using LVM.  grep -Ri lvm
/etc/nixos returns nothing, and all my logical volumes appear under
/dev/disk/by-label and /dev/<vg name>

James