Hello @binariesindia ,
Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.
I understand that you would like to know how to setup a Basic SKU VPN gateway.
If you are trying to create a new VPN gateway, then you can select the "Basic" SKU in the VPN gateway creation page on Azure portal as below:
Refer: https://learn.microsoft.com/en-us/azure/vpn-gateway/tutorial-create-gateway-portal
If you have an existing VPN gateway and you would like to change it to Basic, then this may not possible via a re-size option.
As mentioned in the below doc, with the exception of the Basic SKU, you can resize your gateway to a gateway SKU within the same SKU family. For example, if you have a Standard SKU, you can resize to a HighPerformance SKU. However, you can't resize your VPN gateway between the old SKUs and the new SKU families. For example, you can't go from a Standard SKU to a VpnGw2 SKU, or a Basic SKU to VpnGw1 and vice-versa.
Refer: https://learn.microsoft.com/en-us/azure/vpn-gateway/vpn-gateway-about-skus-legacy#resize
The resizing of VpnGw SKUs is allowed within the same generation, except resizing of the Basic SKU. The Basic SKU is a legacy SKU and has feature limitations. In order to move from Basic to another SKU, you must delete the Basic SKU VPN gateway and create a new gateway with the desired Generation and SKU size combination.
Refer: https://learn.microsoft.com/en-us/azure/vpn-gateway/point-to-site-about#gwsku
Basic SKU is supported on Generation1 only. If you have a Generation1 Standard SKU VPN gateway, then re-sizing to Basic SKU may work.
To change any other existing VPN gateway SKU to Basic SKU, you need to delete the existing VPN gateway and create a new VPN gateway.
Refer: https://learn.microsoft.com/en-us/azure/vpn-gateway/vpn-gateway-about-skus-legacy#change
Kindly let us know if the above helps or you need further assistance on this issue.
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