question

@SaurabhGada-0698 Welcome to Microsoft Q & A Community Forum. I understand you are trying to trigger on demand back up of azure vm using PowerShell. You can use below commands to trigger the on-demand backup for a virtual machine.

Here is a sample script to trigger an on-demand backup. This script assumes that you have enabled system assigned identity for automation account. Also, enable appropriate RBAC permissions to the system identity of this automation account. Otherwise, the runbook may fail.

 try
 {
     "Logging in to Azure..."
     Connect-AzAccount -Identity
 }
 catch {
     Write-Error -Message $_.Exception
     throw $_.Exception
 }
    
    
 Get-AzRecoveryServicesVault -Name "<recoveryvault name>" | Set-AzRecoveryServicesVaultContext
    
 $namedContainer = Get-AzRecoveryServicesBackupContainer -ContainerType AzureVM -Status Registered -FriendlyName "<azurevmname>"
    
 $item = Get-AzRecoveryServicesBackupItem -Container $namedContainer -WorkloadType AzureVM
    
 $job = Backup-AzRecoveryServicesBackupItem -Item $item 

References:

• Get-AzRecoveryServicesVault
  

• Set-AzRecoveryServicesVaultContext
  

• Get-AzRecoveryServicesBackupContainer
  

• Get-AzRecoveryServicesBackupItem
  

• Backup-AzRecoveryServicesBackupItem