Subject: Re: [summary] virtio network device failover writeup

From: "Michael S. Tsirkin" <[email-masked]>
Date: Tue, 19 Mar 2019 17:19:55 -0400

On Tue, Mar 19, 2019 at 08:46:47AM -0700, Stephen Hemminger wrote:
> On Tue, 19 Mar 2019 14:38:06 +0200
> Liran Alon <[email-masked]> wrote:
> 
> > b.3) cloud-init: If configured to perform network-configuration, it attempts to configure all available netdevs. It should avoid however doing so on net-failover slaves.
> > (Microsoft has handled this by adding a mechanism in cloud-init to blacklist a netdev from being configured in case it is owned by a specific PCI driver. Specifically, they blacklist Mellanox VF driver. However, this technique doesn’t work for the net-failover mechanism because both the net-failover netdev and the virtio-net netdev are owned by the virtio-net PCI driver).
> 
> Cloud-init should really just ignore all devices that have a master device.
> That would have been more general, and safer for other use cases.

Given lots of userspace doesn't do this, I wonder whether it would be
safer to just somehow pretend to userspace that the slave links are
down? And add a special attribute for the actual link state.

-- 
MST