Migrate config from dotfiles

hosts/helios/README.md

@@ -0,0 +1,38 @@
+# Helios
+
+## Overview
+Dell OptiPlex 980 small form factor desktop.
+
+## Specs
+* CPU - Intel Core i7-860 @ 2.8GHz
+* Chipset - Intel Q57 Express
+* Memory - 8 GB DDR2
+* GPU - AMD FirePro 2460
+* NIC - Intel Gigabit 82578DM
+
+### Disks
+Device | Partitions _(filesystem, size, usage)_
+--- | ---
+SanDisk Ultra II | `/dev/sda1` (ext2, 200 MiB, NixOS Boot) <br> `/dev/sda2` (ZFS, 480 GiB, NixOS Root)
+
+> Note: The BIOS firmware on this machine only supports booting from disks with
+> an MBR partition table.
+
+#### ZFS pool layout
+```
+rpool/
+├── local
+│   ├── nix
+│   └── tmp
+├── system
+│   ├── root
+│   └── var
+└── user
+    └── home
+```
+
+See [Graham Christensen's article](https://grahamc.com/blog/nixos-on-zfs/#datasets) for the motivation behind these datasets.
+
+### Networks
+- DHCP on `192.168.1.0/24` subnet.
+- Tailscale on `100.64.0.0/10` subnet. FQDN: `helios.mesh.vimium.net`.