Steps:

1. In a terminal such as bash or PowerShell, login to Azure with the az login  command and choose the appropriate subscription that contains the Azure Flexible Server as a resource.
   
   

   Login to the Azure CLI

   az login

2. It's assumed that you already have a virtual machine running Redgate Monitor that will be used as the Base Monitor for your Flexible Server instance. If you already have a system-assigned managed identity enabled for the virtual machine you can use the following command to retrieve its object ID, which will be used later:
   
   

   Retrieve VM object ID

   az vm list --query "[?identity.principalId != null].{name:name, vmObjectId:identity.principalId}"
   
   # Example command output:
   [
     {
       "name": "redgate-monitor-vm",
       "vmObjectId": "12b356de-1728-498c-9488-58902e913d48"
     }
   ]
   

   
   If you have not already added a system-assigned managed identity to the virtual machine running Redgate Monitor, you can do so using the following commands:
   1. First, retrieve the resource ID
      
      

      Retrieve the VM resource ID

      az vm list --query "[].{name:name, resourceId:id}"
      
      # Example command output
      
      [
        {
          "resourceId": "/subscriptions/e11e87fh-ga1f-005a-bb79-d7b375fcff35/resourceGroups/redgate/providers/Microsoft.Compute/virtualMachines/Monitor",
          "name": "Monitor"
        }
      ]

   2. Then use the resource ID from the previous command to assign the system managed identity, and take a note of the "systemAssignedIdentity" from the response:
      
      

      Assign the managed identity

      # Change the "resourceId" below to the one retrieved from the previous command
      
      az vm identity assign --ids "resourceId"
      
      # Example command output
      
      {
        "systemAssignedIdentity": "12a536dc-1a38-b98c-9488-58902e913d48",
        "userAssignedIdentities": {}
      }

      
      
      
3. It also necessary to retrieve the resource ID for the Azure Flexible Server instance, which will act as the scope for our role. You can do that with the following command, which will list the Flexible Server instances and their resource IDs:
   
   

   Retrieve the resource ID

   az postgres flexible-server list --query "[].{name:name,flexResourceId:id}"
   
   # Example command output
   [
     {
       "flexResourceId": "/subscriptions/f71d87ce-fa7f-405b-bb77-d7b375fcff34/resourceGroups/redgate/providers/Microsoft.DBforPostgreSQL/flexibleServers/azureflex",
       "name": "azureflex"
     }
   ]

4. Using the virtual machine's object ID from step 2, as well as the resource ID for your Azure flexible server instance from step 3, we can assign the built-in "Monitoring Reader" role to your app registration, which will give it access to the metrics of the database instance.
   
   

   Assign a role

   # Replace 'vmObjectId' in the command below with the virtual machine's object ID, and 'flexResourceId' with the resource ID retrieved in previous steps.
   
   az role assignment create --assignee "vmObjectId" --role "Monitoring Reader" --scope "flexResourceId"

   
   Optionally, if you wish to monitor a number of instances on the same resource group or subscription, you can increase the scope by only including the relevant sections. For example:
   
   

   Assign a role with a greater scope

   # To give permission to monitor all instances in a resource group:
   az role assignment create --assignee "vmObjectId" --role "Monitoring Reader" --scope "/subscriptions/f71d87ce-fa7f-405b-bb77-d7b375fcff34/resourceGroups/redgate"
   
   # To give permission to monitor all instances in a subscription:
   az role assignment create --assignee "vmObjectId" --role "Monitoring Reader" --scope "/subscriptions/f71d87ce-fa7f-405b-bb77-d7b375fcff34"
   

5. You should now be able to use advanced monitoring for your Azure Flex instance in Monitor.