docs: add prerequisites

docs/deployment/prerequisites.md

@@ -1,3 +1,55 @@
 # Prerequisites
 
-TODO
+## BIOS setup
+
+> You need to do it once per machine if the default config is not sufficent,
+> usually for consumer hardware this can not be automated
+> (it requires something like [IPMI](https://en.wikipedia.org/wiki/Intelligent_Platform_Management_Interface) to automate).
+
+Below is my BIOS setup, your motherboard may have a different name for the options, so you'll need to adapt it with your hardware.
+
+```json
+{
+    "Devices": {
+        "Network Setup": {
+            "PXE IPv4": true,
+            "PXE IPv6": false
+        }
+    },
+    "Advanced": {
+        "CPU Setup": {
+            "VT-d": true
+        }
+    },
+    "Power": {
+        "Automatic Power On": {
+            "WoL": "Automatic"
+        }
+    },
+    "Security": {
+        "Secure Boot": false
+    },
+    "Startup": {
+        "CSM": false
+    }
+}
+```
+
+## Update config files
+
+Gather the following information:
+
+- [ ] MAC address for each machine
+- [ ] OS disk name (for example `/dev/sda`)
+- [ ] Network interface name (for example `eth0`)
+- [ ] Choose a static IP address for each machine (just the desired address, we don't set anything up yet)
+
+[Fork this repo](https://github.com/khuedoan/homelab) and update these config files based on those information:
+
+- [ ] `metal/hosts.yml`
+- [ ] `metal/group_vars/all.yml`
+- [ ] TODO git config in `bootstrap/...`
+- [ ] TODO single place for Ingress domain
+- [ ] (Optional) TODO single place for docs link config
+
+TODO single place for all config, maybe a `./config` directory with some symlinks?