TinyPilot: Build a KVM over IP for Under $100 | Hacker News Reader

TinyPilot: Build a KVM over IP for Under $100

tinypilotkvm.com

196 pointsBrajeshwar73 comments

I prefer pikvm instead. They support cheap HDMI to CSI boards that have lower latency. And they don't make you pay for some features like tiny pilot does. This site sounds like a hobby one but it's actually a commercial product.

TinyPilot founder here. TinyPilot also supports HDMI to CSI bridges. They're included in the pre-made TinyPilot Voyagers:

https://github.com/tiny-pilot/tinypilot/wiki/HDMI-Capture-De...

Ok that's interesting.

I still don't think I'll use it though. I can understand you're trying to make a business out of it. But the password protection feature is one that's too big to do without even in my home network.

For the other stuff like remote mounting drives I can imagine you're asking money for. But the password is pretty essential IMO, as is HTTPs. And the license drives the price far above $100.

Nevertheless I wish you luck with your business!

Fwiw I think pikvm is going the same route now, selling premade hardware. It's nice but the price is just too high for hobbyists. Some of my servers didn't even cost me $200 new and that's with iLO included.

Hey Michael, what do you think of building an HDMI-to-UVC device? Basically a device integrated in a cable with 2 ends: HDMI and USB. It would capture the video output of a computer, emulate a USB video class (webcam) device so the USB end can be plugged into another computer which would be able to see the video output of the other computer using any standard webcam software.

Heck it could even be powered by the USB host. It would be an "active cable" that doesn't require any custom software. Would be super convenient to carry with a laptop for data center technicians.

Such a device exists and can be bought from Amazon for less than 20 dollars. Keyword USB HDMI Capture.

These things tend to be buggy though, I have had a litany of bad experiences. If you want quality, go for the stuff that Blackmagic Design sells - yes, it's about 5x more expensive than bottom-of-the-barrel crap on Amazon that's actually rebranded or dropshipped crap from Alibaba, but it actually works.

For KVM stuff it will suffice.

Not really if its USB stack just locks up after a couple of hours and needs to be manually power cycled to work again.

Haven't had that problem.

Awesome! Last time I looked into, many years ago, this did not exist. Thanks!

Server-class motherboards like the Asrock EP2C603 have built-in management that allows controlling power and usually kvm-like access to the system, via the network. I don’t think I’ve ever plugged a keyboard and monitor into my server after the first time (to set up the iLO thing itself). If you’re building a home server from scratch the right choice of motherboard can save you the need of yet another box to wrangle. Tiny Pilot is still really cool :)

For home-systems that run idle most of the time, the problem with Intelligent Platform Management Interface IPMI is the power consumption of the Baseboard Management Controller BMC which is, if I remember well, around 8Watt. That is more than a carefully tweaked 12Volt-only Motherboard + idle CPU like those of Fujitsu eg the D3644-B https://www.kontron.com/en/products/d3644-b-uatx/p157722

If you're looking for a KVM over IP for a hobby project with a Intel CPU you might want to first check to see if your CPU supports Intel AMT/vPro. If you enable this then you get a built in KVM over IP without any additional hardware/software. Once setup you can connect via a VNC client.

I tried this with a few HP desktops I was going to use as a homelab, but I found it flaky. I used MeshCommander but I never got a stable workflow. I wanted to be able to reinstall with PXE. Somehow the vPro failed to connect when booting into BIOS.

If anyone is interested in how the author built it and what software it runs we chatted about it a while back on my podcast: https://runninginproduction.com/podcast/105-tinypilotkvm-let...

No mention of chroma sub-sampling for either pikvm (M-JPEG) or tinypilotkvm (H.264).

I have an Apple Pro Display XDR and it's just not worth the hassle trying to use it with Linux or Windows machines. Instead, I plan to use an HDMI capture device to get 1080p windows on a Mac. OBS's [guide](https://obsproject.com/forum/resources/capture-card-document...) shows some devices that capture RGB at 1080p60 like the $170 AVerMedia Live Gamer Ultra (GC553) and $300 Magewell XI100DUSB-HDMI. Uncompressed 24bpp x 1920 x 1080 x 60 is almost 3 megabits/second, so OK for USB SS, but not great for networking over a distance, but my application doesn't need remote.

Would NDI (https://www.ndi.tv/ ) work or am I not understanding your requirement?

It's around 200mbps for 60Hz 1080p but if you are just going from a local PC to a local mac it won't matter much

I have 3 PiKVMs and I love them.

https://pikvm.org/

Came here to mention the pikvm. Slightly more expensive but much more well rounded.

> “for under $100”

Maybe back in the day when rPis weren’t as hot a commodity as a high end video card or a latest gen gaming console. Yes, I’ve bought rPis this year for MSRP, but only if you consider the amount of time I spent monitoring sites like rpilocator to be “free”.

So many raspberry pi projects here today, and so little (zero, 0) Pis available to buy :/

Really? I've bought 2 pi zero 2's and one pi4 (4gb) this year. I did have to look around a bit but it was pretty quick. (In EU)

https://rpilocator.com/

It seems that only rpi3 a+ are available in two stores, only one in EU

If you find me available rpi 4s in stock in EU, i'm ordering 5 right now :)

What I did was order from kubii.es (though the main store is .fr) and even though they were on backorder they came through within a week or 2. YMMV but not immediately on hand doesn't mean unavailable.

I really appreciate the sentiment behind Rpilocator, but it really ruined things for those of us who knew which sites to scan for Rpi stock, by exposing availability to the masses. I have not been able to locate a single RPi4 through the usual channels since Rpilocator became live. Luckily, there is one source that the author missed, but it is wasteful and expensive. Cannot wait for the supply chain issues to be resolved.

They often find a few 3 B+, or a few 4 B, or a few Compute Modules available, but usually for < 30 minutes. Follow on Twitter or set up some alerts if you really need a Pi right now. Hopefully it lets up someday :(

> The Pi 4 needs 3 Amps for stable operation, though it can run at lower power. A computer's USB 3.0 port provides only 0.9 Amps and USB 2.0 provides only 0.5 Amps [...]

> To solve this problem, I worked with an engineering firm to create a custom circuit board that splits the Pi's USB-C port into two. The first port accepts USB power, so you can still deliver a full 3 Amps to the Pi. The second accepts USB data out, so the Pi can still impersonate a USB keyboard.

OK, but this makes it sound like the Pi is just the wrong computer for the task. Surely there's some other SBC that just has native external power and can do USB OTG.

I think you can just power the pi via pins on the header unless this no longer works on the pi 4?

Yes but you still need to cut the power wires from the managed machine to avoid back feeding afaik.

Depends on the workload.

> Every few months, I'll screw something up and prevent the server from booting or joining the network, effectively locking me out of the machine. To get things running again, I have to disconnect everything, drag the server over to my desk, and juggle cables around to connect the server to the keyboard and monitor at my desktop.

It's worth a couple hundred extra dollars to get a server motherboard with a management port. Just open a web browser to the management IP and it has a KVM.

All my newer servers use server motherboards. The older ones before I learned, always take extra effort.

I mean, IPMI is nice, and I'd love to have it, but a thrift store monitor ($20-$50?) and a $10 keyboard is an acceptable emergency console as long as you've got space to put it near the server. And you save money on every build. Now, if someone would make an IPMI add-in card or cheap IPMI boards, I would probably do that. I'm also going to take a look at the vPro stuff mentioned elsewhere in the thread (and I think AMD has something similar)... that might work enough and may be available on inexpensive parts??

I've just replaced the main board in my storage machine with a supermicro board, and although the ipmi web UI isn't great, it still allows me to fix issues without having to dig out the monitor and keyboard I used to keep around for things like this.

Do any of the server motherboard manufacturers (I’m thinking Supermicro, I don’t know who else sells ~1) make mini-ITX boards? I’d like to have remote management for my NAS, but I don’t have space for something larger than the mini-ITX case I have.

My last one was a ROMED8-2T from Asrock Rack. They have a catalog with standard and also weird motherboards(mine came with 7 PCIev4 slots because it's a GPU server, and 6 of them had dedicated lanes to the CPU. Most motherboards try to share bandwidth with a PCIe switch, so not ideal for machine learning)

A quick search shows 2 Intel motherboards with mini-ITX form. There was also a micro-ATX.

https://download.asrock.com/Download/e-catalog/ASRockRackPro...

I've also bought from Gigabyte before. The selection isn't as good, but I see an AMD and 3 Intel with mini-ITX. You might have to get separate embedded versions of the processors.

https://www.gigabyte.com/Enterprise/Server-Motherboard

I think Intel has more options with smaller boards here. Always check the block diagram to see if the IO matches how you'll use it.

Also if you want specifically a NAS, get a prebuilt model from e.g. QNAP and it will come with a management interface already.

I got this one for $600:

https://www.amazon.com/gp/product/B08FB5LBJP

If you outgrow a 9-bay NAS, they also sell full storage servers with management.

I was very tempted to build a NAS too, but ultimately prebuilt was better I think.

Yes. Basically any motherboard Supermicro release which has F in the model means, that there is IPMI which allows remote management. X10, X11 and X12 motherboards have html5 viewer, which doesn't require java. I just ordered X11SCL-IF for my NAS and it is mini-itx. There are couple from Asorck rack available as well, and also mini-itx and with ipmi.

Anyone has experience making Raspberry Pi talking with server via RS232 serial interface? I am well aware that most servers/desktops have serial interfaces, but those are way of different kind of breed than what raspberry Pi has. I am going to order RS232 TTL MAX3232 serial port converter and try to build such a poor mans KVM device. Idea is quite simple, really - once server boots back up after extended power outage where UPS tried its best, its 99% going to make it to at least GRUB prompt or even kernel boot, if no hardware damage have been done, where it's going to ask for LUKS passphrase to unlock encrypted devices. Here I have setup initramfs with dropbear sshd with static IP to ssh into remotely, but it would also be nice that raspberry pi sitting nearby could talk with kernel over serial link. I have so far configured GRUB and kernel to talk serial and it works fine in VM setup with virtual serial interface, so it's now a matter of acquiring correct hardware for this to work. All should be about of a cost of one old rasbperry pi (even first model will do) and 10 bucks for serial converter.

EDIT: for a few extra dollars it's also possible to cycle motherboard reset/power switch with Raspberry Pi and something called optical relay switch, as described here - https://github.com/xtensa/PyControlPC and video after the break: https://www.youtube.com/watch?v=MFxcdinrOAo

> Anyone has experience making Raspberry Pi talking with server via RS232 serial interface?

I have:

- two Dell R710

- Raspberry Pi 3

- Raspberry Pi 4

- Several x86 machines

- StarTech.com USB to RS232 DB9 serial adapter [0]

- RS232 serial header adapter [1]

- DB9 cable [2]

The StarTech.com USB adapter seems to work well. I haven't had any trouble with it whatsoever.

I will say that I'm very unimpressed with serial interfaces in general but especially of Dell's BIOS output. Sure, they're aged... but serial is aged way older. Dell's firmware would often write to parts of the 80x24 screen which were already displaying something else and make it practically impossible to read what's going on. It seemed to especially occur when starting different sections of hardware. When the Dell firmware would start up, it would fill the interface with a text-display showing status and what's about to load. It would offer "press key to configure". When it goes to load drivers for netboot/disk/etc, it wouldn't clear the screen. Netboot would write its output on top of the "press key to configure" interface. Then drivers for the disk would write on top of _that_. Further, the configuration interface would sometimes wrap some of the fields to the next line and garble that line. And finally, the interface simply _didn't work at all_ if it wasn't at 9600baud. So input/output slow af. And the text would all be garbled if the serial bit rate were misconfigured with regards to 7/8 data/parity or check bits or etc (but that's to be expected). The problems with Dell's BIOS output to serial are difficult enough to work with that I would not try to use it to try to debug it outside of academic exercise. My time's worth more than that.

On the other hand, I have used it work with the bootloader (grub) before the kernel has loaded. I successfully used the serial interface to diagnose and repair a driver problem with a video card on an desktop that I had. I had a straight DB9 cable connected to a pair of motherboards who had serial interface headers. I'd connected a header adapter and a straight DB9 cable and encountered a lot of the same problems. That was a fun, albeit trying, experience because it involved a lot of reboot cycles which are quite time consuming. There were still a lot of similar problems with regards to overwriting parts of the interface that hadn't been cleared but they weren't nearly as numerous as with Dell's BIOS output.

[0]: https://www.newegg.com/p/N82E16812400121

[1]: https://www.newegg.com/startech-icusb232int1-usb-to-db9/p/N8...

[2]: https://www.newegg.com/p/12K-01CJ-00009

The IOGEAR 2-Port Cinema 4K DisplayPort KVM (GCS62DP) is about $200 CAD.

https://www.amazon.ca/gp/product/B01BSNSOPU

Switches adequately between Linux and non-Linux operating systems, with both desktop environments set to 4K resolution at 60 Hz. Truly plug-and-play. Any $100 DIY solution will be a great learning experience. If you consider time as an expense, DIY solutions will likely cost north of $300 CAD.

AFAICS the device in your link does not support IP functionality at all (remote console access), which is what TinyPilot is for.

I have been looking for a solution where I can remote into my company laptop in a pinch from my phone. Many of our cloud resources are moving to be private IPs and VPN only, which can only run on corporate managed devices. I have a few PIs sitting around and it seems like it would be $100-$200 even with a PI to build (pikvm hat is $150 and tinypilot wasn't obvious what the BOM is).

Is there a lower cost or simpler solution? Company hardware is windows and VPN is fortinet and WSL2 is allowed

The cheapest secure option with built-in software is probably SSH port forwarding of RDP. If you have to, you can have an SSH client connecting out from the laptop, reverse port forwarding back from a server you control.

Ideally you'd configure RDP to only listen on loopback.

Any software solution would be detectable to all the corporate monitoring tools vs. hardware as discussed in the article (which I guess someone could figure out via USB/device IDs but seems less likely to be noticed than open ports/RDP connections).

> Next, I looked at commercial KVM over IP solutions. They provide similar functionality to Dell's iDRAC, but they're external devices that connect to a computer's keyboard, video, and mouse ports (hence the name KVM). Sadly, they're even more expensive, ranging in price from $500 to $1000 per unit.

And the site's commercial product is $400, which is also quite expensive.

https://tinypilotkvm.com/product/tinypilot-voyager2

    $389.99
    Add AC to USB-C Power Adapter - US ($9.99)
    Add VGA to HDMI Adapter ($14.99)
    Choose version:
    Standard: Supports USB-C power
    PoE: Supports USB-C or PoE power (+$59)

Nifty! This was mentioned in the "Building a Budget Homelab NAS Server" article that was on the front page earlier: https://news.ycombinator.com/item?id=31548829

(I want this, now I just have to find a Raspberry Pi)

I just saw this post as well and I was already dreaming about all of the troubles this would have saved me in the past giving tech support to my mother who is 3000km away.

She has a chromebook, which doesn't allow interaction-less remote control which is a huge pain. So much so that I will set her up with a Macbook air next time I am there.

Tinypilot seems like a good solution as well. Though for a laptop it seems like there could be some physical troubles on her end to connect it, etc. Maybe usb-c might be a good alternative at some point of both mouse, keyboard and video could go over the same cable.

One problem with such a setup might be that you'd need the display to be mirrored or either you or your mother might not see what you're doing. You can work around that by spamming ctrl+F4 (the screen mirror configuration switch shortcut) but if you need to give tech support, that may not be an option.

There's also the need for the device to have decent internet. You can probably set it up to work quite comfortably over WiFi, but if the WiFi password changed somehow you'll need to mess with ethernet, which can be a pain for the person receiving support.

You're probably much better off just using https://remotedesktop.google.com/ if you want to remote control the device. I don't know the exact situation of your mother, of course, but I imagine having her read a code off a screen will be much easier than having her hook up your special remote control device the right way.

All good but the idrac comparison is a little faulty. I purchase used dell 630/730/830s often. Idrac card used is around $20-50 max. Used servers are around $200 including idrac...

Correct me if I'm wrong, but I believe those idrac cards only work on compatible Dell servers. So it really isn't a catch-all solution for most people like these ip KVM Solutions.

Correct. But with idrac you can also wake on lan 100%. Idrac never sleeps. Other solutions are difficult because of this reason. This doesn't mean I don't use KVM. Not every company has Dell or HP servers with idrac or similar solutions.

Most consumer motherboards have wake on lan. Though, admittedly, the incantations to get it working can vary between boards and can be difficult to figure out sometimes.

That is correct, you can only use iDRAC in a Dell server. Other manufacturers have similar BMC solutions, but it's really a built-in item and not something you can just pop into the PCI slot of your custom-built tower.

Are there solutions that allow you to do this for more than 1 server?

I‘d like to be able to choose one of the servers in the rack to access and not buy & manage one of these devices for every server.

You can hook these up through a regular kvm switch that allows you to use a single mouse, keyboard, monitor with more than one system. But you should read up a little before purchasing. Only certain switches will work correctly to switch servers using a keystroke combo. I have read that some didn't seem to work with a virtual keyboard like this tinykvm.

Yes, that's what a remote KVM switch (or, KVM-over-IP) does.

Here's a vendor with a lot of options: https://www.kvm-switches-online.com/kvm-switch-over-ip.html

Purchase a used enterprise KVM and some dongles. They are $10k+ new, but only hundreds used.

Can I just pay someone to make me one of these (or a pikvm)? I just basically need a way to enter in preboot authentication text remotely into my Windows PC. I have a used single port KVM over IP that works "somewhat" but I have a feeling it won't be useful when I actually need it.

I know several companies that have a need for HDR capable KVMs. Imaging you're making an OS/Browser/Game that supports HDR. You want to run continuous integration / testing machines that test that your HDR actually works and makes it to the screen (not just what your read-back tells you).

Anyone know of any?

I bought an old Raritan KVM-over-IP for home use and it's pretty pretty good. The software is old but it's enterprise and "just works".

You just need to stick with VGA video to keep the cost down. As soon as you start going to HDMI that's when it gets expensive.

But it uses java right?

It does, but I repacked their viewer to use a bundled Mac JVM and it acts like a native (though slightly ugly) application.

I have two of them now. They work great. Very happy to support a small indie developer.

Splurged on the Raritan 101, after I was unimpressed with the PiKVM's framerate. I use it to keep my work laptop in a closet to reduce noise and desk clutter. One of the best $500 I've spent.

Open Source software KVM for Linux/Windows/Mac:

https://github.com/debauchee/barrier

It looks more like vnc or Remote Desktop than, say, something you could use to configure bios settings or other stuff at boot.

Yeah, this doesn't crack the same nut at all.

Is there anything like that that supports 4K60 with minimal lag?

I've been looking for the same, it's come down throwing some $$'s at dedicated 4k@60 HDMI/DisplayPort extenders and using a soft KVM like Barrier [0] for mouse and keyboard. I haven't found any hardware specs that include latency figures, an occasional "no latency" claim.

[0]: https://github.com/debauchee/barrier

Probably for $600

I wonder if Raspberry Pi could just have been underclocked to reduce power consumption instead of USB power / data splitter.

The original author here is using a Pi 4 which is well known for being pretty fast and hot. One easier way to solve the power usage problem would just be to not use a Pi 4. Something like a Zero 2W might be able to pull it off since it has a quad core cortex A53 SoC which runs with dramatically less power. The Cortex A72 in the Pi 4 is great but it is a comparatively very large processor compared to the A53 (you even often see A72-A53 big-little SoC configurations for this reason. GPU acceleration might become necessary for high performance video streaming but iirc the VideoCore IV on the Pi is pretty okay, especially for transcoding.

Wouldn't it be possible to keep the Pi alive by connecting to the 5V header pin directly (and possibly using a diode)?

are there KVM devices capable of switching a multi-monitor setup with HDMI/DP ports? I couldn't find any a few years ago

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