BASIC SKU static public IP of an azure virtual machine to STANDARD SKU static public IP

Madhusudan 26

We initially assigned a BASIC SKU static public IP to an Azure virtual machine, but since the BASIC SKU is being retiring, we have switched to a STANDARD SKU static public IP for the same machine. After making this change, the machine is no longer accessible via RDP, and the website is also unreachable, despite updating the necessary DNS records in GoDaddy.

0 comments

Answer accepted by question author

Jilakara Hemalatha 13,945 Microsoft External Staff Moderator

Hi Madhusudan,

After investigating the RDP connectivity issue, here’s what we found and recommend for connecting to your Azure VM via the secondary public IP and private IP.

When you add a second public IP to your VM’s network interface, the VM needs to “know” about the corresponding secondary private IP. This requires manually adding the secondary private IP inside the VM’s network settings. Without this, RDP connections to the secondary public IP won’t work because the VM isn’t listening on that address.

Could you please follow the below steps:

Use the primary IP to log into the VM.
Open the network connections settings (ncpa.cpl), find your network adapter.
Go to Properties → IPv4 → Advanced → IP Addresses.
Add the secondary private IP address and subnet mask.
Confirm the changes and verify with ipconfig that the new IP appears.
Ensure your firewall and Network Security Group (NSG) allow RDP (port 3389) traffic. Note: In below path enter the primary Ip details from ipconfig all and DNS server (168.63.129.16 default)
```
  And, in advanced add the secondary private Ip address.
```

After this, you should be able to connect via RDP using the secondary public IP.

Note:
Secondary Private IP: Your computer must be on the same Azure VNet or connected via VPN to access the VM.

Secondary Public IP: Can be accessed from anywhere on the internet, just like the primary IP.

Please refer below official documentations:

https://techcommunity.microsoft.com/blog/itopstalkblog/step-by-step-adding-multiple-ip-addresses-to-an-azure-virtual-machine-with-power/2677513

https://learn.microsoft.com/en-us/azure/virtual-network/ip-services/virtual-network-multiple-ip-addresses-portal#os-config

I have reproduced the issue it was worked for me. Hope this helps. Please let me know if you have any queries.

Jilakara Hemalatha 13,945 Reputation points Microsoft External Staff Moderator

2025-09-24T16:11:34.4233333+00:00

Hi Madhusudan,

As you mentioned issue was resolved after performing above steps. Kindly consider accepting the answer and upvote it to assist other community members.

Answer recommended by moderator

Madhusudan 26

Final solution

The Basic SKU Public IP was dissociated from the VM using the Azure Portal.
A Standard SKU Public IP address was created and associated with the VM’s existing private IP address through the Azure Portal. This private IP was originally assigned dynamically within the Azure VM’s operating system.

This resolved the issue of assigning a Standard Public IP to the VM.

To assign an additional Public IP to the VM, a secondary private static IP address was added to the network interface via the Azure Portal.
Another static Public IP address was then created and associated with the secondary private IP address via the Azure Portal.
Inside the Azure VM, the primary IP address, default gateway, and DNS settings — which were previously assigned dynamically — were manually configured with the same values to make them static. This step was necessary to allow the assignment of the secondary IP address.
The same secondary private IP address (created via the Azure Portal) was then configured within the Azure VM operating system.

0 comments

1 additional answer

TP 156.8K Reputation points Volunteer Moderator

2025-09-23T04:42:15.9433333+00:00

Hi,

Please confirm that you have inbound rules for TCP 3389 (RDP), TCP port 443, and TCP port 80 for the Network Security Group (NSG) associated with your VM's network interface or subnet. Standard SKU Public IPs are secure by default which means you need to specifically allow the incoming ports you need.

Please navigate to your VM in Azure portal, on left click on Networking -- Network settings. If you don't already have an NSG for your network interface or subnet you may click Add network security group button, otherwise click Create port rule -- Inbound port rule to create new inbound rule.

If you are unsure how to create NSG and/or necessary inbound port rules, please add comment below and I will assist further.

Please click Accept Answer and upvote if the above was helpful.

Thanks.

-TP
Was this answer helpful?

1 person found this answer helpful.
Madhusudan 26 Reputation points

2025-09-23T06:05:59.8733333+00:00

NSG for network interface is already there and the ports are also already opened

TP 156.8K Reputation points Volunteer Moderator

2025-09-23T07:17:38.18+00:00

Thanks. How did you upgrade the IP to Standard? Normally the public IP and DNS records don't need to change. Since you mentioned updating DNS records I'm assuming the public IP changed?

Did you re-Associate the Public IP Address with the VM's network interface after you upgraded it to Standard SKU?

When you attempt to connect via RDP, have you double-checked you are connecting to the new Public IP? You probably already did but I ask just in case.

1. As a test, please create a new VM (if you don't have one already) attached to same virtual network and subnet. Select Azure Spot discount so that the cost is minimal. Once this VM is up and running, connect to it via RDP, and then open mstsc.exe inside of the VM and see if you are able to connect to the problem VM's private IP address.

Did this nested remote desktop connection succeed or fail? Close the nested Remote Desktop Connection window.

2. Still within the test VM, please open PowerShell prompt and test to see if you can connect via TCP 443 to the problem VM's private IP address. Command would be similar to below (10.0.0.4 is sample private IP for problem VM):

Test-NetConnection 10.0.0.4 -Port 443

Did test succeed or fail?

The goal of above quick tests is to see if the issue may be related to the public IP or if the VM itself isn't accepting connections for some reason. When finished testing you can disconnect RDP and Deallocate the test VM. Later when you have your VM working again you can delete the test VM and its related resources.

If you are unsure how to do something I mention above please let me know.

What other troubleshooting steps have you performed so far? For example, resetting the VM's NIC, redeploying, flow logs, IP flow verify, etc. Knowing what you have done already may help.

Thanks.
Sign in to comment

Use comments to ask for clarification, additional information, or improvements to the question.

Share via

BASIC SKU static public IP of an azure virtual machine to STANDARD SKU static public IP

1 additional answer

Your answer