waagent: enable provisioning

[Atry]

Description of changes

Currently there are two issues in Azure provisioning:

1. Provisioning in waagent was disabled in waagent: update to 2.8.0.11 #206974 because provisioning always failed.
2. Azure VM will timeout after 90 seconds when mounting /dev/sr0 during restarting an Azure VM, because /dev/sr0 is only available the first time starting an Azure VM.

This PR fixes provisioning in waagent and enables it.

Things done

• Switched Python version to 3.9, because waagent 2.8.0.11 is not compatible with Python 3.10. See [BUG] traceback.format_exception - 3.10 compatibility Azure/WALinuxAgent#2753
• Removed the call to self.osutil.conf_sshd because it will try to modify /etc/sshd/sshd_config and raise an error about read-only file system
• Stopped mounting /dev/sr0 because it should be handled by waagent

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 23.11 Release Notes (or backporting 23.05 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md.

[Atry]

Note that the code to read CustomData.bin is obsoleted. Nowadays there is not such file at all.

[Atry]

The patch is downloaded from https://github.com/Atry/WALinuxAgent/commit/383e7c826906baedcd12ae7c20a4a5d4b32b104a.patch

[zimbatm]

Looks good, but I don't have a machine to test it right now.

Going forwards, please limit the number of people you request for review, so it's proportionate to the amount of code you change.

[Atry]

Looks good, but I don't have a machine to test it right now.

I am using this PR to build images, which work well on Azure

[Mic92]

Can one of you test this by chance? @henrirosten @AkechiShiro
I don't have an Azure subscription and the last time I did, it screwed up my microsoft account.

[AkechiShiro]

Hi @Mic92 @Atry how can this be tested on Azure, an NixOS image must be built and uploaded to Azure and then booted as a VM ?

[Atry]

@AkechiShiro

1. I use https://github.com/nix-community/nixos-generators to create the vhd file
2. Then I uploaded the vhd file to Azure Blob Storage
3. Then I created a VM Image from the vhd on the Azure Blob Storage
4. Then I created a VM from the VM image

[Atry]

@AkechiShiro @Mic92 Any updates?

If you don't have time to manually test it on Azure, do you trust me enough to merge this PR, given that it works for me.

[AkechiShiro]

Hi @Atry, I'm sorry but I couldn't easily test it, I'd need a temporary throwaway account (it's a bit of a pain to setup just for testing this PR)