How to assign public ip directly to virtual network interface (virtual machine)

John 0

Hello!

How to assign public IP directly to virtual network interface (or virtual machine). I need it for IPsec that specifically does NOT work behind NAT (or if it does, Azure does not have the tools to work around that). Port mappings (forwarding) won't work. As an example on a simple VM - Oracle Virtualbox - there is the option to have a NAT network or Bridged network. I could not find any such function on Azure.

I could not find any instances mentioned here: https://learn.microsoft.com/en-us/answers/questions/938566/how-to-assign-public-ip-to-virtual-machine-scale-s

I also can't create a network interface without it being in virtual network. A virtual network also has to have a private address subnet. I am pulling out my hair. Please help me. Thank. You.

Ramya Harinarthini_MSFT 5,346 Reputation points Microsoft Employee

2023-08-14T13:00:14.44+00:00
Hi John

Public IP addresses are associated to the network interfaces that are attached to Azure VM.

Sign into the Azure portal.

In the portal, search for and select the VM that you want to add the public IP address to.

Under Settings in the left pane, select Networking, and then select the network interface you want to add the public IP address to.

Note

Public IP addresses are associated to the network interfaces that are attached to a VM. In this screenshot, the VM has only one network interface. If the VM had multiple network interfaces, they would all appear, and you'd select the network interface you want to associate the public IP address to.

From the Network interface window, under Settings, select IP configurations*, and then select an IP configuration from the list.

Note

Public IP addresses are associated to the IP configurations for a network interface. In this screenshot, the network interface has only one IP configuration. If the network interface had multiple IP configurations, they would all appear in the list, and you'd select the IP configuration that you want to associate the public IP address to.

Select Associate, then select Public IP address to choose an existing public IP address from the drop-down list. If no public IP addresses are listed, you need to create one. To learn how, see Create a public IP address.

Select Save, and then close the IP configuration window.

Note

The public IP addresses that appear in the drop-down list are those that exist in the same region as the VM. If you have multiple public IP addresses created in the region, all will appear here. Any address that's already associated to a different resource is grayed out.

From the Network interface window, view the public IP address assigned to the IP configuration. It might take a few seconds for a newly associated IP address to appear.

Note

An IP address is assigned from the pool of public IP addresses reserved for an Azure region. For a list of the address pools used in each region, see Azure IP ranges and service tags. If you need the address to be assigned from a specific prefix, use a Public IP address prefix.

Open the necessary ports in your security groups by adjusting the security rules in the network security groups. For information, see Allow network traffic to the VM.

Reference Article: https://learn.microsoft.com/en-us/azure/virtual-network/ip-services/associate-public-ip-address-vm#azure-portal
John 0 Reputation points

2023-08-14T15:32:27.47+00:00

Unfortunately if I run #ip a command in linux terminal in said virtual machine the output would be 10.0.0.4 with no mention of 20.120.31.90 which is exactly the problem I have. Thanks for the long answer but it is not what I need.
Ramya Harinarthini_MSFT 5,346 Reputation points Microsoft Employee

2023-09-06T06:22:27.0666667+00:00

John •

Just checking in to see if the below answer helped. If this answers your query, do click "Accept the answer” for the same, which might be beneficial to other community members reading this thread. And, if you have any further query do let us know.
Ramya Harinarthini_MSFT 5,346 Reputation points Microsoft Employee

2023-09-07T15:33:04.4666667+00:00

John •

Just checking in to see if the below answer helped. If this answers your query, do click "Accept the answer” for the same, which might be beneficial to other community members reading this thread. And, if you have any further query do let us know.
Ramya Harinarthini_MSFT 5,346 Reputation points Microsoft Employee

2023-09-11T06:59:24.74+00:00

John •

Just checking in to see if the below answer helped. If this answers your query, do click "Accept the answer” for the same, which might be beneficial to other community members reading this thread. And, if you have any further query do let us know.

1 answer

msrini-MSFT 9,281 Reputation points Microsoft Employee

2023-08-21T19:17:47.01+00:00

Hi,

In Azure, SDN takes care of the Public IP to the private IP mapping. Azure VM's guest OS doesn't even know its public IP. To create IPSEC tunnel, between your on-Prem and Azure VM, you can simply use the Public IP of your VM as peer and provide the IP address range of your VNET as the peer IP space.

Regards,

Karthik Srinivas
Please sign in to rate this answer.

0 comments No comments
Sign in to comment

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

Share via

How to assign public ip directly to virtual network interface (virtual machine)

1 answer

Your answer