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Invalid MAC address prefix!!!!

[ Edited ]

Why doesn't the MAC address OUI or prefix shown on the Dashboard for an airCube-isp match the MAC address OUI that is actually used?

 

On the Dashboard, the MAC address OUI is 78:8A:20, but the MAC address OUI that the device actually uses is 7A:8A:20.  The 7A:8A:20 shows up in both the discovery and in arp.

 

I've noticed that some airCube-isp devices do not seem to want to pick up the IP address assigned to them in the dhcpd.conf file and pick up one from the default pool instead.

 


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Emerging Member
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Registered: ‎07-28-2017
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Re: Invalid MAC address prefix!!!!

[ Edited ]

It's a locally administered MAC address (it's still a valid MAC address).

 

The standards for MAC addreses allow for both registered OUIs and locally administered ones.

They also define whether a MAC address is for unicast or multicast.

Devices are free to assign additional MACs where they have multiple interfaces as long as they remain unique at later 2.

 

Whereas a multicast or reserved MAC address would be invalid or "bogus" in this context.

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Member
Posts: 157
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Re: Invalid MAC address prefix!!!!

I believe it's the LAN mac address you see. The WAN Mac is different than the sticker and UI. Usually one number is different in the middle of the MAC. The current box of 20 I have on hand have a 56 in the middle of the MACs on the stickers, but the WAN is 57.

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Re: Invalid MAC address prefix!!!!

That might well be the case.  The radio only shows one MAC address on the display.  It is quite possible that it is reading the one address correctly and only the other MAC address has an invalid OUI.

 

The OUI should be normally be the same for both addresses.  I can see that there could be two differnt OUIs registered for the same company on a router, but we would never expect to see one MAC address using a valid OUI and the other using an OUI that is unassigned.

Member
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Registered: ‎02-16-2017
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Re: Invalid MAC address prefix!!!!

[ Edited ]

Our units all run in router mode, I only see one MAC

New Member
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Re: Invalid MAC address prefix!!!!

I haven't bothered to look at the airCubes, but the airRouter uses the same MAC address for LAN0 and LAN1.  So on an airRouter, a computer connected by ethernet would see the same MAC address from either side.

New Member
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Re: Invalid MAC address prefix!!!!

It's not just the one router.

 

I'm setting up another right now and found the same problem.

 

The MAC address on the dashboard is: FCECDA5C4F1C.  So the OUI is FCECDA which is assigned to Ubiquiti Networks.

 

The MAC address that it actually uses is FEECDA5D4f1C.  This OUI is FEECDA which is apparently not assigned to anyone as of yet.

 

Note the '5C4' is for the wifi  and the '5D4' is for the ethernet.  But the FEEECDA should obviously be FCECDA.

New Member
Posts: 25
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Re: Invalid MAC address prefix!!!!

I guess we aren't going to get an explanation for this embarassment?

 

Close the eyes and hope nobody notices that they are sending out equipment with bogus MAC addresses?

Emerging Member
Posts: 88
Registered: ‎07-28-2017
Kudos: 30
Solutions: 9

Re: Invalid MAC address prefix!!!!

[ Edited ]

It's a locally administered MAC address (it's still a valid MAC address).

 

The standards for MAC addreses allow for both registered OUIs and locally administered ones.

They also define whether a MAC address is for unicast or multicast.

Devices are free to assign additional MACs where they have multiple interfaces as long as they remain unique at later 2.

 

Whereas a multicast or reserved MAC address would be invalid or "bogus" in this context.