If this box is unplugged from my ER-X, and I then plug in my notebook into the RJ45 wan port, then can I guarantee that my notebook will get DHCP an address? Because right now when the notebook is plugged into the wan port I can give it a 10.90.0.nn address to log into the router in an emergency.
and this must be uncommented: #option network 'lan'
Expanding a bit, the name of the network is lan, not br-lan.100. All of your SSID config stanzas have similar issues. Use the actual network names (lan, vlan200, vlan300, vlan400), not the device names.
Why is it called a network in the wireless file, but an interface in the network file?
wireless:
option network lan
network:
config interface lan
I am lost.
I made those wireless changes anyway and restarted the network (init.d).
Ref network file changes:
Why do I want the IP inside my management lan when the TPLink will DHCP an IP from the ER-X when connected, and use it's own address when disconnected and I plug my notebook into the wan port?
Also, I still think that I will lose access to the Rj45 wan port if I change the IP address.
Truthfully, I don't know. Probably some historic/legacy reason with some parts while other bits have changed terminology over time.
The interface in the /etc/config/network file is the "Network Interface" which is synonymous with simply "Network." It is a layer 3 (routed) construct. There are physical interfaces (ethernet, wifi, bridges; sometimes virtual devices like VPN tunnels) which are defined by the device term -- these are layer 2 (switching) entities. The network interface connects to the devices in order to be available to the outside world.
We attach the wifi SSIDs to a "network," not a device. That is why we connect to lan (network interface) and not br-lan.100 (bridge device).
That is what I expected. The port may be labeled “wan” but it is really just a port.
That is expected. The device functions as a bridged ap. It does not have a dhcp server or anything else happening, it just provides an Ethernet to wifi bridge. It requires a router upstream to work (your er-x).
Correct. You can only have a single dhcp server on the network, so we disable it on the ap and let the actual router do all the work.
Since there is just one port, it is either lan or wan. It cannot be both at once. Wan is usually the internet, whereas lan is typically the connection behind your router. As a bridged AP, we want it on your lan.
Openwrt has wifi disabled by defualt. On single port devices, the Ethernet port is setup as a lan port so that you can gain access to the device (the wan, usually exposed to the internet, is treated as untrusted and therefore you cannot access the router from the wan).
