test and improve direct ethernet instructions

1 files changed, 40 insertions, 14 deletions

diff --git a/readme.md b/readme.md
index 0a96337..c21b853 100644
--- a/readme.md
+++ b/readme.md
@@ -37,27 +37,53 @@
 
 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.
+This allows you to `ssh` into the BeagleBone, as well as share your internet
+connection (even eduroam!) 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:
+2. Run `nmcli device` on your computer, note the name of the **connection** on
+   the ethernet port:
 
    ```
    $ nmcli device             
-   DEVICE         TYPE      STATE                   CONNECTION 
-   enp0s25        ethernet  connected               enp0s25    
-   wlan0          wifi      connected               wifi       
-   lo             loopback  connected (externally)  lo         
+   DEVICE         TYPE      STATE                                  CONNECTION
+   wlan0          wifi      connected                              eduroam
+   enp0s25        ethernet  connecting (getting IP configuration)  Wired connection 1
+   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.
+   (the automatically generated name `Wired connection 1` is the ethernet
+   connection to the BeagleBone)
+3. Run the following command to enable sharing on this port (replace NAME with
+   the connection name you found).
+
+   ```
+   $ nmcli connection modify NAME ipv4.method shared ipv4.addresses 192.168.2.2/24
+   ```
+
+   This assigns the ip address 192.168.2.2 to your computer, and gives the
+   BeagleBone an address in the 192.168.2.0/24 range (edit this only if it
+   conflicts with another subnet).
+4. Run the following command to   to activate the connection.
+
+   ```
+   $ nmcli connection up NAME
+   ```
+
+5. (Optionally) use `nmap -sn 192.168.2.0/24` **as root** to find the IP
+   address the BeagleBone got, or just connect to the BeagleBone using the
+   hostname you configured before (in `/etc/hostname` on the BeagleBone).
+6. Profit
+
+When you're done doing stuff on the BeagleBone, and want to reverse all the
+above changes, simply run:
+
+```
+$ nmcli connection delete NAME
+```
+
+NetworkManager will automatically re-configure the ethernet connection for
+regular use the next time you plug in an ethernet cable.