How to turn anything into a router • Hacker News Board

Re: How to turn anything into a router

#131

Post by yabones » Mon, Mar 30, 2026, 5:45 PM UTC

fio_ini wrote: post #48

I am truly sorry. I can't understand the physical networking from the pics or the description... I'm probably just missing something. There is one blue plug going from the laptop to the cisco switch or the pci wifi module? I see a blue plug going to each device. So I'm guessing everything is plugged into the cisco switch? if you could show all the wiring and label it (according to the table below) i think it would ad…

Hey, op here, this was almost a decade ago, but I'll try to describe what's going on here. It's kind of a crappy picture.

* WAN connection comes in by coax, into my cheapo cable modem (off screen), and then by Ethernet into the franken-NIC sitting on top of the laptop.

* The NIC on top is a normal PCIe card, but with the bracket missing. The ExpressCard riser [1] is connected by a mini-HDMI cable, the flat black cable, which curves up, around, and back in from the left side into the laptop

* Then, the blue cable on the side of the laptop is a VLAN trunk going into the Cisco switch on port 23/24, outside the picture.

* From there, another port on the switch is setup as an access/untagged port going into one of the LAN ports on the D-Link acting as the access switch

I don't think it was set up here, but at one point I also had a dock under the ThinkPad, with the serial adapter wired up to the switch's console port so I could manage everything by ssh'ing into the router.

[1] https://www.ebay.com/itm/115721630079

Also note that all the cables were hand-crimped because I was too cheap to buy new patch cables at the time.

I was in college, and truly had more time than money back then. it's the kind of doohickey made by only somebody very young, very crazy, or a bit of both. ;)

Re: How to turn anything into a router

#132

Post by yabones » Mon, Mar 30, 2026, 5:46 PM UTC

zoobab wrote: post #45

Love the "An ExpressCard-PCIe bridge in the ThinkPad’s expansion bay". Would you have a picture of the ExpressCard laptop connector?

It would be something a bit like this: https://www.ebay.com/itm/115721630079

Before Thunderbolt was common, people attempted to use external GPUs with this sort of expander, but it worked really poorly.

Re: How to turn anything into a router

#133

Post by supertrope » Mon, Mar 30, 2026, 5:46 PM UTC

pdntspa wrote: post #109

Can anyone recommend a good, energy-efficient, inexpensive dual-NIC SBC or miniPC? Last time I looked into this there were not many good options.

A used Sophos XG 115. Has Intel Ethernet interfaces which is preferable for BSD compatibility. 8W idle. I power it off a 802.3af to 12V splitter.

If you want maximum speed a Lenovo Thinkcentre m720q has a desktop Intel CPU and a PCIe slot. You can add a 2x SFP+ NIC and PCIe riser to get 10G.

Re: How to turn anything into a router

#134

Post by ndsipa_pomu » Mon, Mar 30, 2026, 5:49 PM UTC

stavros wrote: post #54

VorpalWay wrote: post #49

Earlier quoted context omitted.

Pfsense/opnsense would be one option (based on FreeBSD). For Linux there is OpenWRT, which you can either run as an alternative firmware on quite a few consumer routers/access points, or install on a PC or Pi or similar. Caveat: I have only used OpenWRT on a high end consumer router (GL.inet MT6000) out of those. That works well, anything else is based on reading about people using those options. For all of those, on…

Nice, thanks! I had an OpenWRT router back in the day, but it had no Web interface. I'll try OPNsense, thanks.

OpenWRT has the LuCI web interface you can add to it (often included in installs) which lets you do pretty much everything.

Re: How to turn anything into a router

#135

Post by pak9rabid » Mon, Mar 30, 2026, 5:49 PM UTC

bluedino wrote: post #47

This really takes me back. My first actual 'use' for Linux was making routers out of leftover computers. The perfect machine back then was a 100MHz Pentium, in a slimline desktop case. At the time, the Pentium III was the current desktop chip, so you'd have a pile of early Pentium-class machines to use. And even a 10mb ISA network card (3Com if possible) would have plenty of power for the internet connections of the…

Hell, you could do this with a single NIC if you have a VLAN-aware switch.

Re: How to turn anything into a router

#136

Post by tibbydudeza » Mon, Mar 30, 2026, 5:50 PM UTC

Nobody I know makes routers and more importantly WiFi combo AP in the US except for high end corporate stuff - even the US only cable modem stuff from Comcast are Chinese OEM ???.

Some more idiocy from the FCC chair.

Re: How to turn anything into a router

#137

Post by seniorThrowaway » Mon, Mar 30, 2026, 5:53 PM UTC

bityard wrote: post #116

jasonjayr wrote: post #34

Earlier quoted context omitted.

I agree on principal, but I often find that the GUI abstractions don't always map to the linux tooling/terminology/concepts, which often ends with a head bashing against the wall thinking "this is linux, I know it can do it, and I can do it by hand, but what is this GUI trying to conceptualize?!?!" I was recently introduced to a Barracuda router, and bashed my head against the wall long enough to discover it had an s…

I guess I'm different. I typically want my router/firewall/network services box to Just Work. I've made a career in deep-in-the-weeds system administration and engineering. Having to hunt down man pages, examples, tutorials, etc for the dozen or so fiddly bits make up a modern Linux- (or BSD-) based router was fun the first time, not so much the 10th. Been there, done that, got the t-shirt. I will concede that the Op…

I feel almost exactly the same as you on the subject. When I was young and starry eyed I built my own router out of a PC running openBSD, all by hand. Nice learning experience, interesting OS, but definitely not maintenance free especially around system updates as back then openBSD packages and sys upgrades required recompiling everything. Now I do the same mini-PC thing as the OP's article but I just put OpnSense on it. Agree the UI can be maddening at times but the thing is rock solid, and has very polished update and upgrade mechanisms. Built-ins/plugins are great - unbound, wireguard, openvpn suricata, backups to git etc. Also I like that it is BSD based, my network experience was learned on Cisco's and Junipers in an ISP setting and Linux networking has always driven me crazy

Re: How to turn anything into a router

#138

Post by hughes » Mon, Mar 30, 2026, 5:55 PM UTC

I wonder if consumer routers will end up being built in a trivially-not-a-router configuration - something akin to a pull-tab or turn of the screw that closes a circuit, transforming the device from legally something else into a router after it's purchased.

What a dumb timeline.

Re: How to turn anything into a router

#139

Post by seniorThrowaway » Mon, Mar 30, 2026, 5:57 PM UTC

lucasay wrote: post #40

“Just use OPNsense” is great advice for production, but terrible advice for learning. This article is valuable precisely because it shows how little magic is actually involved in routing.

SOHO toys don't do routing in a real sense at all

Re: How to turn anything into a router

#140

Post by ndsipa_pomu » Mon, Mar 30, 2026, 5:59 PM UTC

I think the NanoPi range (https://www.friendlyelec.com/index.php?route=product/categor...) has great hardware for making your own router. They support various flavours of Linux, including OpenWRT (or at least their branded version called FriendlyWRT). I like the NanoPi M5 model as it supports using a NVMe so it can happily run some Docker containers on it. The case is really well made and uses passive cooling, so it's ideal for a router.