Modern server platforms support an increasing number of network interface ports on the motherboard (Lan-on-Motherboard or LOM) in addition to numerous add-in (single and multiport) adapters. Traditionally, network interfaces are enumerated as eth[012...], but these names do not necessarily correspond to the actual labels as seen on the chassis. This new naming convention assigns names to network interfaces based on their physical location, whether embedded or in PCI slots. By converting to this naming convention, system administrators will no longer have to guess at the physical location of a network port, or modify each system to rename them into some consistent order.

In this classic naming scheme for network interfaces, the kernel simply assigns the names beginning with "eth0, "eth1", ... to all the interfaces as they are probed by the device drivers during the system boot process. As the driver probing is generally not predictable, in a multi network interfaces setup, a given network interface that for example, got a name assignment "eth0" in the first boot may end up with a different name on the next boot. This is undesirable and can have serious security implications, for example in firewall rules which are coded for certain naming schemes and which are hence very sensitive to unpredictable changing names. Also, this naming scheme gives no clue whatsoever of the interface's physical location on the system (for example, whether it is on the system's motherboard or if it is on an add-in card or if it is on an add-in card with multiple ports and which port on the card it is located). Hence you need a consistent device naming scheme that can provide the following benefits:
  • Stable network interface names across reboots
  • Stable network interface names when you add or remove hardware
  • Stable network interface names when you update/change the kernel or device drivers
  • Stable network interface names when you replace a broken/defective ethernet card for example, with a new one
  • The network interface names automatically get determined without user configuration and they just work
  • The network interface names are predictable

During SAP workload provisioning operations, like cloning a VM, it is essential to keep the same network interface names on the target clone system as is available on the source system. In order to do this, you need to enable Consistent Network Device Naming in the source operating system. The next 3 sub-sections describe the specific steps to enable Consistent Network Device Naming on SLES, RHEL and Windows operating systems respectively.