Adding an additional NIC starts from the same blade as adding inbound and outbound rules. To add an additional NIC, you have to follow the given steps:

1. Before adding an additional NIC to the VM, you need to make sure that the VM is in a Stopped (Deallocated) status.
2. Navigate to Networking on the desired VM.
3. Click on Attach network interface, and a new blade will pop up. Here, you have to either create a network interface or select an existing one. If you are selecting an existing interface, simply click on OK and you are done. If you are creating a new interface, click on Create network interface, as shown in the following screenshot:

4. A new blade will pop up where you have to specify the following:

• • Name: The name of the new NIC.
  • Virtual network: This field will be grayed out because you cannot attach a VM's NIC to different virtual networks.
  • Subnet: Select the desired subnet within the virtual network.
  • Private IP address assignment: Specify whether you want to allocate this IP dynamically or statically.
  • Network security group: Specify an NSG to be assigned to this NIC.
  • Private IP address (IPv6): If you want to assign an IPv6 to this NIC, check this setting.
  • Subscription: This field will be grayed out because you cannot have a VM's NIC in a different subscription.
  • Resource group: Specify the resource group to which the NIC will exist.
  • Location: This field will be grayed out because you cannot have VM NICs in different locations.

5. Once you are done, click Create.
6. Once the network interface is created, you will return to the previous blade. Here, you need to specify the NIC you just created and click on OK, as shown in the following screenshot: