RouterStation LAN Ports UnBridge

[serif]

I am trying to configure a RS with a couple of WiFi cards, a LAN connection, as well as an NS2 & NS5 hung off the remaining 2 ethernet ports. I have no problems with eth0, but I cannot seem to unbundle (unbond, unbridge) the other ethernet ports from each other. I can communicate to eth1, but do no see where I can configure an eth2 interface.

Help is appreciated.

[UBNT-Mike.Taylor]

Serif,

There are two MAC in the AR7100-series processors.

mac0/eth0 is connected to a dedicated port on the switch chip, configured to look like a PHY to the CPU. This port basically passes through to the real PHY driving the link on the WAN jack. This port inside the switch chip is isolated from the other ports internal to the switch and cannot be bridged inside the switch chip by configuration.

mac1/eth1 is connected to a different port on the switch chip, which also looks like a PHY to the CPU. This time, however, the "PHY" we see from the CPU side is really bridged with *ALL* the LAN ports on the switch.

The way that this kind of arrangement works is that the switch port can either make the bridging of all LAN ports transparent OR can automatically handle VLAN tagging and untagging of traffic. By using VLAN tagging, you can assign each port to a different VLAN tag. Then the CPU can sort out the traffic by the tag as to which port it arrived on or needs to leave on. If you are using VLANs yourself, fortunately it even allows for 'double tagging'.

The simplest path is provided by default. eth1 acts like a network connection to a small switch. This is how most platforms are implemented on OpenWRT, though it does support switch configuration for at least one platform.

It's really very easy to do this, but I wanted to keep it simple. This way, the mac is detected and eth1 works right out of the box with no mystery.

If you want to configure more advanced stuff, look at the datasheet and see what is possible. You can modify the mac driver on the chip ("ag7100") and write a few more registers to set it up the way you like. Then you can create eth1.2 and eth1.3, for example and know which jack the traffic is coming in/out of. (You configure these tags to be stripped when the traffic leaves the RS).

I can probably provide you with more specifics if you decide this is something you want to pursue.

Thanks,

Mike