Yep exactly! Setting up a raspberry pi low-performance computing cluster with secondary usb nics, going slowly insane trying to figure out why the vlan interfaces wouldn’t work when their base interfaces worked just fine, and going down all of the wrong rabbit holes along the way.

ifupdown2 has a 15-character interface name limit, and the systemd predictable interface naming system uses the mac address for usb nics (giving them a 15-character name), so if you try to create a vlan subinterface of a usb nic using the standard interface.vlan naming scheme on a systemd host, it will fail, and you’ll have to set up systemd network link files to rename the base interfaces to something shorter.

Yes, with the official M16A4 unit being defined as 1/100th the length between the goal lines of an American Football field.

The ups has data output to my firewall/router via usb, which the baremetal servers all connect to via apcupsd. When the ups loses or regains AC power, it broadcasts a message to all of them and they’re each scripted to act accordingly: laptops run on their own batteries, vms migrate over to laptops, non-vital hardware shuts down, etc.

Some laptop battery firmware allows you to force discharge even when connected to AC, and if your laptop can use the tlp recalibrate or tlp discharge commands then yours is supported.

I use this to power my thinkpad servers off of their own batteries during a power outage, to reduce load on my UPS. Great feature.

In my experience, mounting some thinkpad servers to the wall above the rack gives the homelab a very International Space Station feel.

You can! I registered my first account on ml, and moved to sdf, with a third on world as a backup. You can open one on every instance if you want, or more as individual instance rules permit.