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Show HN: TinyPilot – Build a KVM over IP using a Raspberry Pi

(mtlynch.io)
756 points mtlynch | 3 comments | 23 Jul 20 13:56 UTC | HN request time: 0s | source
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ape4 ◴[23 Jul 20 15:13 UTC] No.23928180[source]▶
Sorry to ask but what's it cost to buy a KVM over IP device?
replies(1): >>23928220 #
EvanAnderson ◴[23 Jul 20 15:17 UTC] No.23928220[source]▶
You're not going to find a decent one sub $500. Used devices can be had for less, but most of the older ones I've seen use terrible Java-based clients that are a major pain to get running on modern browsers. For multi-device KVMs you usually have to figure in the prices for the individual interface module dongles that plug into each computer, too.

StarTech makes a USB-to-KVM that looked promising to me, but it's still >$400: https://www.startech.com/Server-Management/KVM-Switches/Port...

replies(1): >>23928747 #
ape4 ◴[23 Jul 20 16:00 UTC] No.23928747[source]▶
Thanks and that StarTech doesn't have HDMI. Maybe its cloud VMs that are removing the need for KVM over IP. I still want it.
replies(1): >>23929072 #
1. AaronFriel ◴[23 Jul 20 16:27 UTC] No.23929072[source]▶
I wouldn't say cloud VMs have removed the need, they've just made infra admins have to live without it. For the most part it's fine on well supported and tested OSes but before the container/kubernetes revolution I managed some personal VMs with esoteric distros in various clouds and so many things have to go right for that to work. A bad update or install of grub, initrd, dhclient, a handful of system services and maybe systemd, or sshd and the machine is effectively dead. You have to attach the disk to another machine to debug it.

A more extreme example was when I went down the rabbit hole of trying to set up remotely unlocked full disk encryption on a cloud, just to see what was possible. This was maybe 4-5 years ago. This involved a pre-boot environment that would run from memory only, packaged into an initramfs and used dropbear as an ssh server to accept a connection.

I really, really wish cloud VMs had virtual KVMs. It turns out, it's really easy to mess this up, and when you do recovery is Non Trivial.

The best I found was that Azure's cloud allows you to connect (read/write!) a virtual serial port via web interface so you can use the Linux serial console to recover. That was a game changer for playing with this. If dropbear failed to come up, I at least got a shell into the pre-boot environment.

replies(1): >>23929536 #
2. rob-olmos ◴[23 Jul 20 17:07 UTC] No.23929536[source]▶
Google Cloud also provides read/write serial ports over SSH: https://cloud.google.com/compute/docs/instances/interacting-... -- but I think AWS still doesn't.

One thing I've ran into was root not having a password since the cloud images are typically SSH key auth only. That was annoying when trying to fix something simple like iptables or entering maintenance mode for a disk check.

replies(1): >>23929631 #
3. AaronFriel ◴[23 Jul 20 17:14 UTC] No.23929631[source]▶
Thank you! I wasn't aware this was possible back then. I'm glad they implemented this.