Implement support for NixOS.

[Phreedom]

Known issues:

• Resource disk is supplied NTFS-formatted by Azure, so ResourceDisk.Format=y does nothing. This doesn't seem to be NixOS-specific.
• "ERROR:Error parsing ExtensionsConfig. Unable to send status reports" is logged regularly due to missing StatusUploadBlob in ExtensionsConfig. Most likely not NixOS-specific.
• WALA can't log to journald. Setting the log file path to /dev/stdout doesn't work because systemd implements /dev/stdout as a socket. http://lists.freedesktop.org/archives/systemd-devel/2015-April/031182.html

[yuezh]

Resource disk is supplied NTFS-formatted by Azure, so ResourceDisk.Format=y does nothing. This doesn't seem to be NixOS-specific.

WALA will recreate file system on resource disk when it is mounted first time.

"ERROR:Error parsing ExtensionsConfig. Unable to send status reports" is logged regularly due to missing StatusUploadBlob in ExtensionsConfig. Most likely not NixOS-specific.

This will happen, if you uncheck "install agent" option when creating the VM.

WALA can't log to journald. Setting the log file path to /dev/stdout doesn't work because systemd implements /dev/stdout as a socket. http://lists.freedesktop.org/archives/systemd-devel/2015-April/031182.html*

Yes, WALA today doesn't support journald. We will add the support in future release

[lizzha]

@Phreedom
Hi Evgeny, have you tested it on NixOS in Azure?

[Phreedom]

On Monday, December 07, 2015 19:36:59 Yue Zhang wrote:

Resource disk is supplied NTFS-formatted by Azure, so
ResourceDisk.Format=y does nothing. This doesn't seem to
be
NixOS-specific.
WALA will recreate file system on resource disk when it is
mounted first
time.

It turns out that new versions of sfdisk spew deprecation
warnings which break the resource disk formatting code. I have
fixed this for NixOS only, because I'm not in a position to test
other distros. Hopefully, you can test this fix and apply it to all
distros which will eventually also get the "noisy" version of sfdisk.

[Phreedom]

@lizzha yes I have tested it extensively

[lizzha]

@Phreedom could you please share us what test you have done?

[Phreedom]

@lizzha provisioning, reporting the state as "provisioned", creating a user, regenerating ssh host keys, wiping the root password, formatting the resource disk and swap. If you want to see it for yourself, I can provide a publicly-accessible blob that you can use to create an image for tests.

[lizzha]

@Phreedom thanks, that would be great if you could share a VHD to us. Could you also share the steps to build the image?

[Phreedom]

@lizzha I have uploaded an image to
https://nixos.blob.core.windows.net/images/nixos-unstable.vhd

You can use azure-cli to deploy it.

Building your own image is unfortunately not that easy. See
NixOS/nixpkgs#3986 (comment)
29

I have just discovered that when you deploy via azure-cli, you get
"Socket IOError [SSL: CERTIFICATE_VERIFY_FAILED] " errors in
waagent.log. You can ignore them for now. It's a trivial nixos-side fix(but
a long rebuild). It doesn't affect any other functionality. Apparently
extension configs get posted when you deploy via azure-cli, so I didn't
test this code path when deploying via NixOps.

[Phreedom]

@lizzha I have fixed the SSL
certificate error when deploying via
azure-cli in nixpkgs
dac2c651098012c96848819c48890c
f158e62caf and updated the image

[LiliDeng]

@Phreedom @lizzha Verify the SSL certificate error issue is resolved.

[colemickens]

I've tested @Phreedom's work. I can confirm that the VHD booted successfully and the agent seems to be working normally. (VHD from: NixOS/nixpkgs#3986 (comment)). I have a script here (https://github.com/colemickens/azure-nixos) that will allow for easy deployment of the VHD using ARM resources.

[lizzha]

@Phreedom sorry for the late response, we're about to merge the pull request as we've done the testing. This PR now has conflict due to the branch update, could you please resolve the conflict so that we could merge it?

[Phreedom]

@lizzha Done!

[jbgi]

Looks like this patch has not been ported to master... :(
How to best proceed to get it in master? Open a fresh PR against master?

[hglkrijger]

Version 2.0 has been deprecated. This would need to be ported to the current codebase in master.