add direct ethernet setup instructions

1 files changed, 28 insertions, 0 deletions

diff --git a/readme.md b/readme.md
index 267fc38..0a96337 100644
--- a/readme.md
+++ b/readme.md
@@ -33,3 +33,31 @@
   command, i.e. to read 'write(2)' use the command `man 2 write`.
 - Use `dmesg` with the `-w` or `-W` option (see man dmesg(1))
 
+# direct ethernet setup
+
+You can use NetworkManager to both share your computer's existing network
+connection and start a DHCP server for assigning IP addresses automatically.
+This allows you to ssh into the BeagleBone, as well as share your internet
+connection over a single direct ethernet connection.
+
+1. Connect the BeagleBone to your computer using an ethernet cable, and make
+   sure the BeagleBone is on. The ethernet port's link lights should start
+   blinking.
+2. Run `nmcli device` on your computer, the shortest device name starting with
+   `enp` or `eth` is likely your ethernet port's name:
+
+   ```
+   $ nmcli device             
+   DEVICE         TYPE      STATE                   CONNECTION 
+   enp0s25        ethernet  connected               enp0s25    
+   wlan0          wifi      connected               wifi       
+   lo             loopback  connected (externally)  lo         
+   ```
+
+   (in my case, the adapter is enp0s25)
+3. Run `nmcli connection modify ADAPTER ipv4.method shared ipv4.addresses
+   192.168.2.2/24` (replace ADAPTER with the ethernet adapter name you found).
+4. Run `nmcli device connect ADAPTER`.
+5. (Optional) run `nmap -sn 192.168.2.0/24` **as root** to find the IP address
+   the BeagleBone got.
+