27 lines
1.0 KiB
ReStructuredText
27 lines
1.0 KiB
ReStructuredText
.. 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.
|