[Cake] Cake on elements of a bridge

[Toke Høiland-Jørgensen]

Pete Heist <pete at heistp.net> writes:

> I happen to also be working on a bridge setup, but it’s different. For
> one, I used fq_codel on a transparent bridge for a couple years in
> production and it worked well, so I trust it also would for cake.
>
> But now, my neighbor will access the Internet through my CPE device,
> but they must have a separate IP obtained through DHCP (i.e. a
> separate MAC address as well), and I want to use cake to manage the
> queue for both of us. I could do this with two routers and a
> transparent bridge, but I want to see if I can make it work with as
> few devices as possible, preferably just one EdgeRouter-X. I had two
> failures thus far:
>
> Fail #1: Do routing for the neighbors on their NS5AC Loco, and use the
> ER-X’s internal switch to bridge the neighbor’s and my WAN interfaces
> to the CPE. Doing cake on switch0 results in my WAN traffic going
> through the qdisc, but unsurprisingly, the neighbor’s traffic passes
> through the switch without going through the qdisc layer.
>
> Fail #2: Use the ER-X’s pseudo-ethernet functionality to add a second
> virtual Ethernet interface to the ER-X’s WAN interface. I could use
> IFB if I got two WAN interfaces working on the same box. This looks
> promising and I can pick up two DHCP addresses on one physical
> interface, but the ER-X doesn’t handle the routing situation where two
> interfaces have the same default router IP. (Using policy-based
> routing, what does it do when next-hop is the same for two different
> LAN subnets?)
>
> There will be a solution here, I just haven’t found it yet. I’m now
> thinking of a setup with a smart switch / VLANs and a transparent
> bridge through two physical interfaces of the ER-X (which only has 5
> ports total), but I’ll figure it out… :)

DHCP relay and normal routing? Or bridging with a kernel software bridge
rather than the hardware switch?

-Toke