Cannot access my services after upgrade from basic to standard load balancer via PowerShell

I'm afraid I don't fully understand all the steps you describe.

In the Portal, I first browse to show my Virtual Machine.

Then, I click Networking / Network settings

Then, I click on that big link for the Network interface / IP configuration

And finally on Network Security Group. Where I see this - saying "None"

It looks like your VM's Network Interface (NIC) has no firewall rules applied, as indicated by the Network Security Group (NSG) showing "None".

However, your VM might still be blocked due to:

1. An NSG attached to the Subnet (common in Standard Load Balancer scenarios).
2. The Standard Load Balancer's default security settings requiring NSG rules at either the Subnet or NIC level to allow traffic.

To resolve this issue, follow these steps:

1. Check the Subnet NSG:

• Navigate to your Virtual Network (VNet) → Subnets.
• Locate the subnet where your VM is situated.
• Check if an NSG is attached to the subnet.
• If yes, click on that NSG and add the needed Inbound Rules (RDP, HTTP, HTTPS).
• If no NSG is attached at the subnet level, you'll need to attach one.

2. Attach an NSG if None Exists:

• Option A: Attach to NIC (Simpler, VM-specific)
• Go to your VM → Networking → Network Interface → Network Security Group → Associate.
• Create or select an existing NSG.
• Option B: Attach to Subnet (Affects all VMs in that subnet)
• Navigate to Virtual Network → Subnets → Select your subnet → Associate NSG.
• Choose or create an NSG.

3. Add Required Inbound Rules:

• Once the NSG is attached (either to NIC or Subnet), add rules for Port 3389 (RDP), 80 (HTTP), and 443 (HTTPS).

This is essential because Standard Load Balancers block all inbound traffic by default. Without an NSG explicitly allowing traffic, your VM will remain unreachable.

Thanks

Sorry, I'm still struggling here and I can't follow all of your instructions exactly. Here is what I have:

Under my Virtual Network / Settings / Subnets, I see this.

Indeed, there is no NSG associated with Subnet-1.

Trying Option A

I go to the VM, but I don't see "Network Interface" as an option, I see "Network Settings". But in the centre here, I do see a "Network interface / IP configuration".

I click on this one. And then, under settings, I see "Network security group".

...but I don't see any option to "Associate".

Trying Option B

Refer to the first screenshot on this post.

I click to select Subnet-1, but I don't see the word "associate" anywhere on the UI.

You will have to explicitly create the NSG Rules to be able to associate it with either of subnet or VM NIC , please follow these steps:

Attach an NSG and Allow Required Ports You can do this in two ways:

Option 1 – Attach NSG to the VM (NIC level)

(Recommended if only 1 VM needs access)

1. Create an NSG
   • In the Azure Portal, search “Network security groups” → +Create.
     • Name it (e.g., My-VM-NSG) and click Review + Create → Create.
     1. Attach NSG to the VM
        • Go to your VM → Networking (or Network Settings).
          • Click the Network Interface / IP configuration link in the center.
            • Click Network security group → select your new NSG → Save.
            1. Add Inbound Rules to the NSG
               • Go to Network security groups → Your NSG → Inbound security rules → +Add:

                 - __RDP__: TCP, Port 3389, Allow, Priority 100
                 
                       - __HTTP__: TCP, Port 80, Allow, Priority 110
                 
                             - __HTTPS__: TCP, Port 443, Allow, Priority 120
                 

Option 2 – Attach NSG to the Subnet (Subnet level)

(Recommended if multiple VMs in the subnet need the same rules)

1. Create an NSG (same steps as above, e.g., My-Subnet-NSG).
2. Attach NSG to the Subnet
   • Go to your Virtual Network → Subnets.
     • Click the subnet where your VM is running (e.g., Subnet-1).
       • Under Network security group, select your NSG → Save.
       1. Add Inbound Rules
          • Same rules as above (RDP, HTTP, HTTPS).

Step 3 – Test

• Try RDP to your VM (mstsc → Public IP) and open your website in a browser.

✅ Summary

• NIC-level NSG = only affects one VM.
• Subnet-level NSG = affects all VMs in that subnet.
• Without these NSG rules, the Standard Load Balancer will continue blocking inbound connections.

Pradeep - thank you so much!

I have now got it working and have verified that RDP works, along with my HTTPS websites. I chose Option 1 as I have only one VM behind the LB.

One thing to note though. My RDP rule has a warning against it.

The warning message is

`RDP port 3389 is exposed to the Internet. This is only recommended for testing. For production environments, we recommend using a VPN or private connection.

Save`