5.3 Virtual NICs

A VNIC is a virtualized Network Interface Card, used by a Virtual Machine as its network interface. A VNIC is assigned a MAC address. Each MAC address corresponds with a single virtual NIC, which is used by a virtual machine. You create VNICs when you create a virtual machine. The Virtual NICs tab is used to display the VNICs assigned to different virtual machines within your environment and to control the MAC addresses applied to each VNIC.

The Virtual NICs tab presents a list of all of the VNICs configured within Oracle VM Manager in tabular format. The following fields are displayed for each VNIC:

  • Name: The name of the VNIC, which is usually the same as the MAC address assigned to it.

  • Virtual NIC: The MAC address of the VNIC.

  • Network: The network that the VNIC is attached to.

  • Assigned to VM: The virtual machine that the VNIC is assigned to.

  • Assigned to VM Template: The virtual machine template that the VNIC is assigned to.

Above the table on the Virtual NICs tab are a set of editable fields that allow you to customize the MAC address range that can be assigned to VNICs as they are generated within your environment. The fields accept valid hexadecimal characters between 00 and FF. The first three fields (octets) represent the Organizationally Unique Identifier (OUI). Changing these fields can cause network conflicts and ultimately network failure and is not recommended. If you edit the MAC address range, you must click the Apply Range button to save your changes. To reset the range, you can click the Reset Range button.

If you select to change the first three octets of the OUI, a warning message is displayed, explaining the consequences of this change, since the MAC addresses assigned to your VNICs can overlap with vendor assigned OUIs. If you proceed to make this change, despite this warning, you receive no subsequent warnings for changing these three octets.

Changing the MAC address range affects the creation of subsequent VNICs during the process of creating or editing a virtual machine. It does not automatically update the MAC addresses already assigned to your virtual machines. To do this, you must edit each virtual machine to change the MAC address there.

For information on creating, editing and removing VNICs on virtual machines, please refer to Section, “Edit Virtual Machine” and Section 3.1.3, “Create Virtual Machine”.


It is important that you do not have overlapping MAC address ranges as this can lead to issues tracing network issues. Oracle VM Manager attempts to prevent the likelihood of this happening by generating unique MAC addresses. However, if you run more than one Oracle VM Manager instance, it is possible that an overlapping MAC address could be generated. If you create a MAC address that is already in the Oracle VM Manager database, an error message is displayed.