Fix for the Subnet Missing Required Delegation - azure

Question

I have a Azure Resource Group and it has a vnet. The vnet has a subnet which has two service endpoints configured namely Microsoft.keyVault and Microsoft.Storage and the subnet also has a subnet delegation to Microsoft.Web/serverFarms.
Now I want to add another service endpoint Microsoft.ServiceBus to the same vnet using Azure Powershell. I executed the below code for that.
$virtualNetwork = Get-AzVirtualNetwork -ResourceGroupName $ResourceGroupName
Set-AzVirtualNetworkSubnetConfig -Name $virtualNetwork.Subnets.Name -VirtualNetwork $virtualNetwork -AddressPrefix $virtualNetwork.Subnets.AddressPrefix -ServiceEndpoint "Microsoft.ServiceBus"
$virtualNetwork | Set-AzVirtualNetwork
But the above code is throwing error at the last line of code saying that the Subnet is missing Required Delegation
Subnet requires any of the following delegation(s) [Microsoft.Web/serverFarms] to reference service association link
StatusCode: 400
ReasonPhrase: Bad Request
ErrorCode: SubnetMissingRequiredDelegation
But in portal I see it has the required delegation. How to fix this error?

Answer 1

Even though i have already added these service endpoint in my specific subnet and subnet also has a subnet delegation to Microsoft.Web/serverFarms able to add another service endpoint Microsoft.ServiceBus.
I would suggest you to use the following PowerShell script:
PowerShell Script:
$subscription = "b83c1edXXXXXXX-XXX"
$subnets = #('TestSubnet')
$vnetName = "Vnet1"
$vnetRgName = "X-rasXXXX-XX"
$newEndpoint = "Microsoft.ServiceBus"
Set-AzContext -Subscription $subscription
foreach($snet in $subnets){
Write-Host "Modifying Service Endpoints for subnet: $snet" -fore red -back white
$virtualNetwork = Get-AzVirtualNetwork -Name $vnetName -ResourceGroupName $vnetRgName | Get-AzVirtualNetworkSubnetConfig -Name $snet
$addrPrefix = $virtualNetwork.AddressPrefix
#Get existing service endpoints
$ServiceEndPoint = New-Object 'System.Collections.Generic.List[String]'
$virtualNetwork.ServiceEndpoints | ForEach-Object { $ServiceEndPoint.Add($_.service) }
if ($ServiceEndPoint -notcontains $newEndPoint){
$ServiceEndPoint.Add($newEndpoint)
}
$delegation=$virtualNetwork.Delegations
#Add new service endpoint
Get-AzVirtualNetwork -Name $vnetName -ResourceGroupName $vnetRgName | Set-AzVirtualNetworkSubnetConfig -Name $snet -AddressPrefix $addrPrefix -ServiceEndpoint $ServiceEndPoint -Delegation $delegation | Set-AzVirtualNetwork
}
Reference : Azure Powershell - Applying multiple service endpoints to a subnet