From 62cf79193a4d7a5c8e6977d2fc792140b0602913 Mon Sep 17 00:00:00 2001 From: rtk0c Date: Mon, 18 Nov 2024 22:42:55 -0800 Subject: [blog] Adventures on server setup without a monitor --- content/blog/adventures-on-monitorless-server.md | 37 ++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 content/blog/adventures-on-monitorless-server.md (limited to 'content/blog/adventures-on-monitorless-server.md') diff --git a/content/blog/adventures-on-monitorless-server.md b/content/blog/adventures-on-monitorless-server.md new file mode 100644 index 0000000..5706b71 --- /dev/null +++ b/content/blog/adventures-on-monitorless-server.md @@ -0,0 +1,37 @@ +--- +title: "Adventures on server setup without a monitor" +date: 2024-11-18T21:41:35-08:00 +--- + +# TL;DR +What happens when you forget to statically assign an IP address to a server running `NetworkManager` or `systemd-netword` or even Debian's default networking setup? +It won't have network connection until IP assigned (because the subnet doesn't have a DHCP in router for example), so no SSH. +But you also don't have access to video output. + +Instead of typing into the TTY hoping for the best, all 3 of the aforementioned systems default to DHCP, and _there is nothing saying a DHCP server has to be running on the router or gateway_. +So, just install and configure `kea` (or a DHCP server of your choice) on any other computer on the network, reboot the server in question, and voilà! +SSH to your hearts content. + +# The story +So the story goes like this. +I recently got hands on a nice little old desktop tower, plenty of RAM and a good number of SATA ports for selfhosting: Seafile, Immich and what not. +Now it _is_ rather old machine, with only VGA and DVI on the motherboard. This means my little trusty HDMI to USB video capture dongle won't be helpful! +I also need to deploy this machine to my parent's house, for I plan on giving them access to a photo backup solution. +I need to bring a monitor that has a VGA port on it. + +So I at the comfort of my home, I took some time to install Debian, as well as all other packages I could possibly need. Also configured a SSH key. + +## Uh oh +And as all good stories go, the _one thing_ I was supposed to do was not done: no monitor, no way to see what's happening on screen to configure its WiFi connection properly. +No network, no SSH-ing either. +For reasons beyond the topic of this story, my parents' router does not have an DHCP server running if connected to the ethernet ports. +I _have_ to connect WiFi or manually set a static IP on the `eth0` interface. + +Quickly, I thought "what if I could just type out all the commands without a monitor?" +Trying to open vim on `/etc/network/interfaces` and blindly modifying a complex configuration file obviously did not work so well. +Although I did figure out one helpful tidbit: since this machine has a beeper, I can run things like `foobar && tput bel` in TTY to get an audio confirmation that something succeeded. + +After ten minutes of desparately trying various commands and questioning if I had been making typos all along, an enlightenment suddenly found its way into my mind: nothing is stopping me from running an ad-hoc DHCP server just for this purpose! +[Kea](https://www.isc.org/kea/) is apparently the recommended implementation, so I installed it on my laptop, and after some fiddling of configs per https://wiki.archlinux.org/title/Kea (because ArchWiki is the one wiki to rule them all), it did work. The server allocates the first address in the pool, so I just picked `192.168.233.1/16` and successfully SSH-ed in. + +No need to drive 30 minutes round trip to get my VGA monitor! -- cgit v1.3.1