farukc/azure-linux-extensions

Linux extensions for Microsoft Azure IaaS

This project provides the source code of Linux extensions for Microsoft Azure IaaS.

VM Extensions are injected components authored by Microsoft and Partners into Linux VM (IaaS) to enable software and configuration automation.

Extension List

Name	Lastest Version	Description
Custom Script	1.3	Allow the owner of the Azure Virtual Machines to run customized scripts in the VM
DSC	1.0	Allow the owner of the Azure Virtual Machines to configure the VM using Windows PowerShell Desired State Configuration (DSC) for Linux
OS Patching	2.0	Allow the owner of the Azure VM to configure the Linux VM patching schedule cycle
VM Access	1.3	Provide several ways to allow owner of the VM to get the SSH access back

Contributing guide

3rd party partners are welcomed to contribute the Linux extensions. Before you make a contribution, you should read the following guide.

1. HandlerManifest.json

The extensions are installed, enabled, disabled, updated and uninstalled by Azure Linux Agent.

You can see these common commands in HandlerManifest.json and take here as an example.

The most important commands:

• The install command is executed only when the extension is deployed the VM for the first time.
• The enable command will enable your configurations (in section 2).

2. Configurations

The configurations include two parts: public configuration and protected configuration.

They are in JSON format and defined in every specific configuration.

How to test

1. Install the extension in your virtual machine on Azure.
2. cd /var/lib/waagent and you can see your extension path.
3. Fix the bug which you found, and test your code change just by re-enabling the extension.
4. Feel free to create your pull request.

Debug

1. The status of the extension is reported back to Azure, and you can see the status on Azure Portal.
2. You can check /var/log/waagent.log to verify if the extension is enabled successfully.
3. The operation log of the extension is /var/log/azure/<extension-name>/<version>/extension.log file.

Known Issues

1. When you run the PowerShell command "Set-AzureVMExtension" on Linux VM, you may hit following error: "Provision Guest Agent must be enabled on the VM object before setting IaaS VM Access Extension".

• Root Cause: When you create the Linux VM via portal, the value of provision guest agent on the VM is not always set to "True". If your VM is created using PowerShell or using the Azure new portal, you will not see this issue.

• Resolution: Add the following PowerShell command to set the ProvisionGuestAgent to "True".

$vm = Get-AzureVM -ServiceName 'MyServiceName' -Name 'MyVMName'
$vm.GetInstance().ProvisionGuestAgent = $true