[TriLUG] Build a Homebrew Linux Router?

[Kevin Otte via TriLUG]

On the good ol' fashioned WRT54G's (and many newer routers such as my
Netgear WNDR3800) with OpenWRT, you could configure each port on the
back to be in a different VLAN. Fairly easy to do through the web UI. At
that point, you put a separate address on each one and configure the
firewall rules to allow certain ones to only egress the WAN and that's it.

In keeping with the topic of this thread, you would need a VLAN capable
switch to plug into your homebrew router. If you're wanting to buy new,
I've been pleased with the TP-Link Jetstream series. These are gigabit,
VLAN capable switches that are manageable over IPv6. There are some less
expensive switches out there that support VLANs and not much else, but
they might do in a pinch.

I've also seen quite a few used managed switches showing up at hamfests
and the like. Many of these are 100 megabit only, likely with a gigabit
uplink or two. I did see a few Cisco 3550 12-port gigabit switches go by
a couple years ago.

If you get a hold of one of these, you can actually do routing on a
machine with a single NIC. We affectionately call this a "router on a
stick". All packets going in and out of the physical interface are
tagged with a VLAN, and the router is essentially just retagging the
frames after a routing decision. This means you only get half the
effective rate (eg: 500 Mbit on a gig interface), but if you're feeding
a bunch of 100Mbit user ports on a gigE uplink, this works great. Of
course, you can combine this with LACP (bonding) and balance all the
traffic coming out of the RoaS and... oh, sorry, I get kinda geeked out
on this stuff.

Perhaps I've put a nickel in someone else and we can back-of-the-napkin
some of this at the next TriChug (or late night parking lot chatter now
that we're back in RTP).

-- Kevin

On 06/14/2016 10:22 AM, Joseph Mack NA3T via TriLUG wrote:
> I was interested as I don't know how to setup
> VLANs on these wifi boxes. I notice Nivex does this on his boxes, but I
> don't know how he does it. I would be more interested in a box with
> VLANs like this.
> 
> Thanks
> Joe
>