Wireless vs Ethernet MAC in MAC tables

We have moved our billing system to Sonar (when they acquired WISPmon). One of the features we are trying to implement is network mapping which they do automatically.  However, we are having an issue with all ePMP APs in getting this to work and it looks like one of the reasons is the Ethernet MAC address of the APs does not show up in the MAC table on our Netonix switches. I find this odd since it is that port that is physically connected to the switch.  The Netonix sees the Wireless MAC but not the Ethernet MAC. I would expect to see both listed.  Is this a Cambium issue or Netonix?  We are running 3.5 firmware on the ePMP and 1.4.8rc12 on the Netonix (latest as of today).

I just looked at one of my sites and see the wireless and ethernet mac addresses listed in the mac table of a netonix switch.  In my case the radio is running 3.2.2 and the switch is running 1.3.7rc7.  I probably should update both of those at some point.

The wireless mac is showing up on my radio management vlan and ethernet mac on the native vlan 1.

radiomac.png

Very interesting. I definately do not show the Ethernet MAC in any of my Netonix switches for the ePMPs.  My firmware is quite a bit later than yours so I don't want to downgrade that far. I see it with ePMP 3.4.1 and 3.5.

Anyone out there running ePMP firmware 3.4.1 or 3.5 and seeing wireless and Ethernet MAC addresses listed in their Netonix switches (for APs)??

The ePMP management interface binds to the wireless interface MAC - you'll never see any traffic coming to/from the ethernet MAC of an ePMP device in bridge mode, as far as we've been able to tell.

Kind of annoying that cnMaestro & other software refers to the devices by their ethernet MAC when the wireless MAC is the one that's usually relevant!

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Thanks for the reply. That will explain why our subscriber modules use the wireless MAC but all our APs only show the Wireless MAC in the MAC table as well - and you can't put an AP in bridge or routed mode, just the SM.  Why would the Ethernet MAC be missing in the MAC table?


@Jacob Turner wrote:

I just looked at one of my sites and see the wireless and ethernet mac addresses listed in the mac table of a netonix switch.  In my case the radio is running 3.2.2 and the switch is running 1.3.7rc7.  I probably should update both of those at some point.

The wireless mac is showing up on my radio management vlan and ethernet mac on the native vlan 1.

radiomac.png



@Au Wireless wrote:

you can't put an AP in bridge or routed mode, just the SM.  Why would the Ethernet MAC be missing in the MAC table?


You can't configure an AP's network mode because APs always run in bridge mode ;) As best we can tell, an ePMP AP never sends any management traffic with the Ethernet MAC as a source address. Always the wireless interface MAC.

Based on what Jacob's seeing above, this might not be the case if management VLAN is enabled, and might not have been the case prior to firmware v3.3? I don't have any radios still running 3.2.2 or older lying around I can check with.

One thing that may be worth checking - if you enable LLDP on the radio, this may cause the ethernet MAC to be detected - though perhaps only with management VLAN also configured.

We have kept LLDP off on all APs to cut down on "chatter". However, after turning it on, I now do see the Ethernet MAC the MAC table on the switch - but it shows up on the un-tagged customer VLAN.  We have always used a management VLAN and that VLAN is attached to all the wireless MACs (AP and SMs).

That'd explain it then! Management packets are sent from the MAC that their logical bridge interface binds to, which Cambium tells me is always the WLAN MAC, so when you're sending traffic to/from the management interface that's the MAC you'll learn.

LLDP changes things a bit - the "link-local" part requires that the source MAC of any given LLDP packet always be the MAC of the physical interface that sent it, and LLDP packets don't need (or, AFAIK, implement) VLAN tagging because an LLDP packet should never be forwarded by a switch/bridge. 

Long story short - flip LLDP on & you'll learn the ethernet MAC on your untagged/data VLAN, because it's actually sending packets with that MAC as the source. Flip it off and you'll only learn the WLAN MAC - either way, on your management interfaces, you'll only regularly see the WLAN MAC & that's exactly what we'd expect to see.

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