Re: [Bridge] [RFC net-next Patch 0/3] net: bridge: mrp: Add support for Media Redundancy Protocol(MRP)

[AsbjÃrn Sloth TÃnnesen]

Hi Horatiu and Stephen,

Horatiu, thanks for giving this a try. I am looking forward to maybe someday
be able to run ERPS on white box switches.

On 1/9/20 4:19 PM, Stephen Hemminger wrote:
> Can this be implemented in userspace?
>
> Putting STP in the kernel was a mistake (even original author says so).
> Adding more control protocols in kernel is a security and stability risk.

Another case is VRRP, ERPS (ITU-T G.8032), VRRP group.

My use-case might not be common, but I have machines with about 10k net_dev (QinQ),
I would like to be able to do VRRP group on the outer VLANs, which are only a few
hundred instances without excessive context switching. I would then keep the the
normal keep-alive state machine in kernel, basically a BPF-based timed periodic
packet emitter facility and a XDP recieve hook. So only setup and event handling
has to context switched to user-space.

Unfortunately I haven't had time to explore this yet, but I think such an approach
could solve a few of the reasons that scalable bridge/ring/ha protocols have to wait
20 years before being implemented in Linux.

--
Best regards
AsbjÃrn Sloth TÃnnesen
Network Engineer
Fiberby ApS - AS42541