Where does one find MAC address for Network Port?

[ThatComplicatedMidiGuyParticipant]

Hey folks!

So I’ve got an install in a pretty locked-down networking environment and we’re trying to ferret out some packet flooding issues. I don’t *think* they’re related to dLive at all, but I need to trace the MAC addresses of our consoles in order to rule them out. I don’t see anything physically printed on either dm48 or our c2500’s, and the Event LOG only seems to show me MAC address for the GigaACe stuff. Any idea where I might find these MACs?

Thanks much!

[ddff_lvParticipant]

Any router or managed switch will show you MAC of connected devices.

ddff

[ThatComplicatedMidiGuyParticipant]

Yeah, that’s the issue. I don’t want to have to unplug the thing and bring in a crap router. 100’s of devices on the existing network and I don’t have admin rights. Was hoping for an easier/lazier solution. 🙂

[JayParticipant]

Midi Guy,

Put a laptop on the same physical network as the dLive.

Get into a Terminal (OSX) or Cmd.exe (Windows) session.

ping [ip address of mixrack] – on OSX you will need to ctrl-c out of it
ping [ip address of surface]
arp -a

Look through the arp output by IP address and you will see the MAC address with it.

Example (not Dlive) from my laptop:
? (172.16.130.8) at 0:17:e0:e8:71:c7 on en0 ifscope [ethernet]
? (172.16.130.223) at a0:99:9b:1b:5c:57 on en0 ifscope [ethernet]
? (172.16.130.227) at ac:87:a3:2:ad:68 on en0 ifscope [ethernet]

My understanding of their Ethernet over GigaACE is a “transparent bridge” so you should see the correct device MAC’s instead of a router MAC. The fact that Dante works across it enforces that.

Jay

[ThatComplicatedMidiGuyParticipant]

Jay!

Thanks man. I’ll give that a go!!

[JayParticipant]

MG,

Make sure only the surface _or_ mixrack are connected to the managed network, never both.

I did quite a bit of network testing earlier this year to make sure I fully understood the capabilities of the dLive network link, and one thing I believe I saw but didn’t write down was the fact it didn’t pass CDP (Cisco discovery protocol). Where this comes in to play is that means it isn’t fully transparent and if CDP won’t pass then spanning tree (STP/RSTP) probably won’t pass, so the switches would not be able to see a loop through the GigaACE if both ends are connected.

The network link over GigaACE is bandwidth limited to about 220MB so, if both ends are connected to an enterprise network, it would probably present itself as an ever-increasing amount of duplicate traffic up to a limit and hold there.

Jay

[ahjeffModerator]

Hi Jay

The GigaACE link itself is fully transparent and performs no packet inspection or filtering of any kind. I’m not sure where your CDP packets could have been going, but the dLive units use a managed switch internally to connect the internal processor, network ports, and GigaACE link. Perhaps this switch could be doing something with those packets, but it should be set up to be as much of a ‘dumb switch’ as possible. The datasheet for the switch is not public, but is there anything in particular that I could look up in it to see if it could be affecting your test?

Cheers

– Jeff, A&H

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