| 5 May 2023 |
 @uep:matrix.org | well, the "init system" part of systemd is | 22:36:18 |
| @uep:matrix.org | So, like, yeah... decouple away | 22:36:37 |
| @uep:matrix.org | At some point in this process, perhaps here where things potentially change between stage 1 and 2, we hit coupling and compatibility issues with a stage 2 that needs to work with scripted stage 1 still? | 22:38:39 |
| 6 May 2023 |
 @mberndt:matrix.org | Hey, so I was looking into making a test for the stratis root fs support that I'm trying to get merged, and I figured that the easiest way to do that is to tweak the lvm2 test that already exists.
https://github.com/NixOS/nixpkgs/blob/master/nixos/tests/lvm2/systemd-stage-1.nix | 16:00:30 |
| @mberndt:matrix.org | But I' confused, because it looks like a logical volume is created in line 90, and then a single file is created in that volume, and then he reboot into that volume | 16:02:19 |
| @mberndt:matrix.org | How can he boot from a volume that doensn't have anything in it? | 16:03:15 |
| @mberndt:matrix.org | * But I' confused, because it looks like a logical volume is created in line 90, and then a single file is created in that volume, and then it reboots into that volume | 16:03:32 |
| @mberndt:matrix.org | * How can it boot from a volume that doesn't have anything in it? | 16:04:51 |
 @elvishjerricco:matrix.org | mberndt: The root fs in nixos tests usually doesn't contain the OS. Instead, /nix/store is mounted as a 9p network file system from the host, so that the VM uses the host nix store instead of wasting time and space on a disk image | 16:06:00 |
| @mberndt:matrix.org | oh wow | 16:06:42 |
| @elvishjerricco:matrix.org | (that's only mostly true; in reality it's usually actually an overlay fs where the lower dir is the 9p file system and the upper dir is in ram or something) | 16:06:44 |
| @mberndt:matrix.org | that's clever | 16:06:48 |
| @mberndt:matrix.org | And so the nix store is already mounted in the initramfs? | 16:07:37 |
| @elvishjerricco:matrix.org | yea | 16:07:46 |
| @elvishjerricco:matrix.org | mberndt: Actually, it looks like that lvm test is currently failing https://hydra.nixos.org/job/nixos/trunk-combined/nixos.tests.lvm2.lvm-thinpool-sd-stage-1-linux-latest.x86_64-linux | 16:11:18 |
| @elvishjerricco:matrix.org | I think probably precisely because it's not doing what I just described :P | 16:11:28 |
| @elvishjerricco:matrix.org | As of recently, useBootLoader implies actually creating a root fs image containing the nix store | 16:11:47 |
| @mberndt:matrix.org | there goes my plan | 16:12:24 |
| @elvishjerricco:matrix.org | let me see if the easy fix for this was implemented... I talked about it with the person who made that change a little while ago but I don't remember if he implemented the fix | 16:13:13 |
| @mberndt:matrix.org | But actually I was thinking that this might not be the best way to test this anyway. After all, what is happening here is that we boot the machine, then set up an lvm2 volume, and then reboot into that. Instead of doing that, maybe it's better to hook into the logic that creates the Qemu VM so that it sets it up with a stratis volume (rather than a GPT partition) to begin with. | 16:15:21 |
| @elvishjerricco:matrix.org | mberndt: You might want to make a variant of the nixos installer test then | 16:15:51 |
| @elvishjerricco:matrix.org | look at `installer.nix | 16:15:54 |
| @elvishjerricco:matrix.org | * look at `installer.nix` | 16:15:55 |
| @elvishjerricco:matrix.org | * look at installer.nix | 16:15:58 |
| @elvishjerricco:matrix.org | actually that's better for a bunch of reasons | 16:16:11 |
| @elvishjerricco:matrix.org | testing actually installing nixos is way more comprehensive | 16:16:23 |
| @mberndt:matrix.org | Thanks, I'll have a look | 16:16:29 |
| @mberndt:matrix.org | Whoa, that's more than 1k lines | 16:16:49 |
| @elvishjerricco:matrix.org | fwiw, this does fix the lvm2 test:
diff --git a/nixos/tests/lvm2/systemd-stage-1.nix b/nixos/tests/lvm2/systemd-stage-1.nix
index b711cd22d7f..05f0e6eb76e 100644
--- a/nixos/tests/lvm2/systemd-stage-1.nix
+++ b/nixos/tests/lvm2/systemd-stage-1.nix
@@ -64,6 +64,7 @@ in import ../make-test-python.nix ({ pkgs, ... }: {
virtualisation = {
emptyDiskImages = [ 8192 8192 ];
useBootLoader = true;
+ mountHostNixStore = true;
useEFIBoot = true;
};
boot.loader.systemd-boot.enable = true;
| 16:16:57 |
| @elvishjerricco:matrix.org | In reply to @mberndt:matrix.org
Whoa, that's more than 1k lines yea well it's actually a bunch of tests in one | 16:17:07 |
