The sub-resource ID /subscriptions/......subnets/dnsin is invalid

joostmnl 0

I have a dnsresolver in a hub vnet deployed with this code:

resource dnsresolver 'Microsoft.Network/dnsResolvers@2022-07-01' = {
  name: 'dnsResolver' 
  location: deploymentLocation
  properties: {
    virtualNetwork: {
      id: hubvnet.outputs.resourceId
    }
  }
	resource inendpoint 'inboundEndpoints@2022-07-01' = {
		name: 'dnsresolverin'
		properties: {
			ipConfigurations: [
				{
					privateIpAllocationMethod: 'Dynamic'
					subnet: {
						id: '${hubvnet.outputs.resourceId}/subnets/dnsin'
					}
				}
			]
		}
	}
	resource outendpoint 'outboundEndpoints@2022-07-01' = {
		name: 'dnsresolverout'
		properties: {
			subnet: {
				id: '${hubvnet.outputs.resourceId}/subnets/dnsout'
			}
		}
	}	
}

In a previous attempt I had this:

esource dnsresolver 'Microsoft.Network/dnsResolvers@2022-07-01' = {
  name: 'dnsResolver' 
  location: deploymentLocation
  properties: {
    virtualNetwork: {
      id: hubvnet.outputs.resourceId
    }
  }
	resource inendpoint 'inboundEndpoints@2022-07-01' = {
		name: 'dnsresolverin'
		location: deploymentLocation
		properties: {
			ipConfigurations: [
				{
					privateIpAllocationMethod: 'Dynamic'
					subnet: {
						id: resourceId('Microsoft.Network/VirtualNetworks/subnets', hubvNetName, 'dnsin')
					}
				}
			]
		}
	}
	resource outendpoint 'outboundEndpoints@2022-07-01' = {
		name: 'dnsresolverout'
		location: deploymentLocation
		properties: {
			subnet: {
				id: resourceId('Microsoft.Network/VirtualNetworks/subnets', hubvNetName, 'dnsout')
			}
		}
	}	
}

And that failed with this response:

The request is invalid, please look into details section for more information. Check the following location for additional guidance: https://aka.ms/azdnsresolver. (Code: BadRequest)

  The sub-resource ID   /subscriptions/../resourceGroups/../providers/Microsoft.Network/VirtualNetworks/vnet001/subnets/dnsout is invalid. It should be a valid Azure resource ID of type Microsoft.Network/virtualNetworks/subnets. (Code: BadRequest)

I would like to understand how the id from resourceId() differs from the success case.

In other words: what is a "sub-resource ID" and why is the id provided by resourceId() invalid?

KapilAnanth-MSFT 35,246 Microsoft Employee

@joostmnl ,

Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.

Thanks for bringing this to our notice.

It appears there is some inconsistency with the resource types "outendpoint" , "inendpoint" and the function resourceId().

I did a lab with resource "nic" and resourceId() , the resource deployed successfully.


var loc = 'centralindia'
var nicName = 'nic'

resource myvnet 'Microsoft.Network/virtualNetworks@2023-04-01' existing = {
  name: 'vnet'
  scope: resourceGroup('rg')
}

resource mysubnet1 'Microsoft.Network/virtualNetworks/subnets@2023-04-01' existing = {
  name: 'dnsin'
  parent: myvnet
}

resource nic 'Microsoft.Network/networkInterfaces@2023-04-01' = {
  name: nicName
  location: loc
  properties: {
    ipConfigurations: [
      {
        name: 'ipconfig1'
        properties: {
          privateIPAllocationMethod: 'Dynamic'
          subnet: {
            id: resourceId('Microsoft.Network/virtualNetworks/subnets', myvnet.name , mysubnet1.name)
            
          }
        }
      }
    ]
  }
}

output check string = resourceId('Microsoft.Network/virtualNetworks/subnets', myvnet.name , mysubnet1.name)

Moreover, the output string correctly displays the resource ID of the subnet.

Also, from the docs,

Users are instructed to use symbolic name for the resource and access the id property

Nevertheless, I shall check this internally and report back as soon as feasible.

Cheers,

Kapil

KapilAnanth-MSFT 35,246 Reputation points Microsoft Employee

2024-04-30T04:29:17.2633333+00:00

@joostmnl ,

To isolate this issue further, we will need a specialized 1:1 session, where a support engineer can have a screen share session to pinpoint the issue.

If you have a support plan you may file a support ticket, else please do let us know, we will try and help you get a one-time free technical support.

Cheers,

Kapil
joostmnl 0 Reputation points

2024-05-03T20:35:48.1766667+00:00

Hi Kapil,

Thanks for the offer support, it is not needed as I managed to deploy the dnsResover using
id: '${hubvnet.outputs.resourceId}/subnets/dnsin'

What I do want to understand is why

id: resourceId('Microsoft.Network/VirtualNetworks/subnets', hubvNetName, 'dnsin')

produces a (Code: BadRequest)

Thanks!