Iterate through a list of VMs in Azure - powershell

Question

i have about 10 VMs hosted on Auzre, i need to iterate through each of them and then execute a powershell script on each of them, lets say 'Set-Date'
whats the best way to connect to each VM, execute the ps script and then disconnect?

Answer 1

You can use PowerShell Remoting or custom scripts via extensions to execute PowerShell code on the remote VM.
For both solutions you get your list of VMs with the PowerShell command Get-AzureVM. Use a loop to iterate those VMs. I skip that part here because iterating are PowerShell basics.
1. PowerShell Remoting
For this you need PowerShell Remoting enabled on the remote VM and have an open port for PowerShell Remoting. Both is a default setting for new VMs.
Advantage: this solution is very handy for interactive sessions with a remote VM. Disadvantage of this solution is, that you need to authenticate to each VM and have to keep connected while execution.
With each VM you can do something like this. This is a shortened example where I have installed ADDS on the remote VM.
# Prepare credentials for remote session.
$secpasswd = ConvertTo-SecureString $AdminPassword -AsPlainText -Force
$credentialDC1 = New-Object System.Management.Automation.PSCredential ($AdminUsername, $secpasswd)
$EndpointDC = Get-AzureWinRMUri -ServiceName testlab-dc -Name dc1
#$EndpointDC = Get-AzureVM -ServiceName testlab-dc -Name dc1 | Get-AzureEndpoint -Name WinRmHTTPs
$psso = New-PSSessionOption -SkipCACheck
$sessionDC = New-PSSession -ComputerName testlab-dc.cloudapp.net -Port $EndpointDC.Port -Credential $credentialDC1 -UseSSL -SessionOption $psso
Invoke-Command -Session $sessionDC -ScriptBlock {
# Set-Date or other command
# or for example
# Install-WindowsFeature AD-Domain-Services
}
Remove-PSSession -Session $sessionDC
2. Custom Scripts via Extensions
Here you can upload a PowerShell file into your BLOB storage and then let execute that file on your VMs. Requirement is that the VM agent has to be installed on the VM. (Default for new VMs from the gallery.)
Advantage: you do not need to authenticate to each VM and you do not need to keep connect while execution.
Disadvantage: you have to prepare a separate PowerShell file to upload. Getting results is asynchronous.
Example:
# Upload PowerShell file
Set-AzureStorageBlobContent -Container extensions -File "Install-ADForest.ps1" -Blob "Install-ADForest.ps1"
# Install AD services and forrest
Get-AzureVM -ServiceName demoext -Name demoext |
Set-AzureVMCustomScriptExtension -ContainerName extensions -FileName "Install-ADForest.ps1" |
Update-AzureVM
The container has to exist. Create that container before you upload the file.