update post (hamnet, pfsense)

content/posts/2022-11-21-hamnet-on-the-pfsense/index.md

@@ -184,6 +184,38 @@ field and save those options.
 
 ![screenshot of the DHCP server options](07_dhcp-server.png)
 
+{{< alert >}}
+**WARNING:** Not all clients will add both the default gateway and the classless
+static routes as per [RFC 3442](https://www.rfc-editor.org/rfc/rfc3442.html#page-5)
+clients must ignore the router option.
+{{< /alert >}}
+
+You will be fine if you use NetworkManager. Connections managed by NetworkManager
+usually add the gateway and the classless static routes.
+
+This is totally different on a Raspberry Pi. These do not use NetworkManager
+(well, maybe they do when they run a desktop environment but not on console).
+The best way (for me) was to ignore the static routes for my Raspberry Pis and
+add the static routes manually.
+
+In `/etc/dhcpcd.conf`, uncomment `classless_static_routes`:
+
+~~~aconf {linenos=inline,linenostart=26,hl_lines=3}
+# A list of options to request from the DHCP server.
+#option domain_name_servers, domain_name, domain_search, host_name
+#option classless_static_routes
+# Respect the network MTU. This is applied to DHCP routes.
+option interface_mtu
+~~~
+
+and let **dhcpcd** add the static routes automatically. Create the file
+`/etc/dhcpcd.exit-hook` and add the routes manually with this script:
+
+~~~bash
+/sbin/route add -net 44.0.0.0/9 gw 192.168.10.1
+/sbin/route add -net 44.128.0.0/10 gw 192.168.10.1
+~~~
+
 ## More resources
 
 * https://support.aa.net.uk/L2TP_Client:_pfSense