Refresh IP address for Azure VM via REST API

Question

I am trying to your the REST API to change the IP of my Ubuntu Virtual Machine on Azure.

In the web interface, stopping and starting the VM usually causes the public IP to change. However, just stopping and starting the VM with curl requests to the API does not trigger an IP change.

I can request the current status of the IP configuration using a GET request (see the docs here ), but I cannot find any function to refresh it. I also tried setting the IP to static and back to dynamic before turning the VM back on, that also did not work.

I found this similar question here , but when I tried that approach, I got the following error message:

{  "error": {
"code": "IpConfigDeleteNotSupported",
"message": "IP Configuration ipconfig1 cannot be deleted. Deletion and renaming of primary IP Configuration is not supported",
"details": []   }

I have also created a secondary IP configuration. The first one is called ipconfig1, the second I named "alternative". This seems to be a second network interface. I have associated a second IP address with that second network interface. But I am still getting the same error.

My final request looks like this:

curl -X PUT  -H "Authorization: Bearer MYTOKEN" -H "Content-Type: application/json" -d '{ "name": "NETWORKINTERFACE542", "id": "GROUP", "location": "westeurope", "properties": { "provisioningState": "Succeeded", "ipConfigurations": [ { "name": "alternative", "properties": { "privateIPAllocationMethod": "Dynamic", "subnet": { "id": "/subscriptions/xx-xx-xx-xx/resourceGroups/GROUP/providers/Microsoft.Network/virtualNetworks/GROUP-vnet/subnets/default" }, "primary": true, "privateIPAddressVersion": "IPv4" } } ], "dnsSettings": { "dnsServers": [], "appliedDnsServers": [] }, "enableAcceleratedNetworking": true, "enableIPForwarding": false }, "type": "Microsoft.Network/networkInterfaces" }' https://management.azure.com/subscriptions/xx-xx-xx-xx/resourceGroups/GROUP/providers/Microsoft.Network/networkInterfaces/NETWORKINTERFACE542?api-version=2020-07-01

(Where the CAPS terms are stand-ins for my actual variable names)

I am still getting the same error, even though I am not even referencing ipconfig1 in my request.

Is there any way to achieve an IP reset?

Answer 1

As your mentioned: In the web interface, stopping and starting the VM usually causes the public IP to change.

Generally, the stop operation in the web UI actually does deallocate operation, so you need to use REST API Deallocate and Start to trigger the public IP address changed.

Virtual Machines - Deallocate

POST https://management.azure.com/subscriptions/{subscriptionId}/resourceGroups/{resourceGroupName}/providers/Microsoft.Compute/virtualMachines/{vmName}/deallocate?api-version=2020-12-01

Virtual Machines - Start

POST https://management.azure.com/subscriptions/{subscriptionId}/resourceGroups/{resourceGroupName}/providers/Microsoft.Compute/virtualMachines/{vmName}/start?api-version=2020-12-01