| .. SPDX-License-Identifier: GPL-2.0 |
| |
| ============ |
| NET_FAILOVER |
| ============ |
| |
| Overview |
| ======== |
| |
| The net_failover driver provides an automated failover mechanism via APIs |
| to create and destroy a failover master netdev and mananges a primary and |
| standby slave netdevs that get registered via the generic failover |
| infrastructrure. |
| |
| The failover netdev acts a master device and controls 2 slave devices. The |
| original paravirtual interface is registered as 'standby' slave netdev and |
| a passthru/vf device with the same MAC gets registered as 'primary' slave |
| netdev. Both 'standby' and 'failover' netdevs are associated with the same |
| 'pci' device. The user accesses the network interface via 'failover' netdev. |
| The 'failover' netdev chooses 'primary' netdev as default for transmits when |
| it is available with link up and running. |
| |
| This can be used by paravirtual drivers to enable an alternate low latency |
| datapath. It also enables hypervisor controlled live migration of a VM with |
| direct attached VF by failing over to the paravirtual datapath when the VF |
| is unplugged. |