GUI Switching / Address table - showing same Interface (port) with different MAC addresses

[astirusty]

Have two GS724TPv2 switches.  When using Web Interface to look at Address table (Under Switching tab), the table shown has same interface (port) shown multiple times, with each time having a different MAC address supposedly connected to it.

For example:

G23 has 00:08:9B:DE:EF:99

G23 has 10:56:CA:63:78:00

G14 has 3C:98:72:FC:9E:DA

G14 has 68:5B:35:CF:7E:1A

G14 has F8:B4:6A:80:90:EC

I have never seen a router or switch show different MAC addresses assigned to same Interface (port).

Rebooting does not clear up Address Table

Internet searches and search here did not turn up the problem.

[schumaku]

These arn't switch port addresses....

On the MAC Address Table section of the Address Table view, there is a tiny (?) stating something like this:

===

Address Table

The Address Table contains information about unicast entries for which the switch has forwarding or filtering information. The transparent bridging function uses this information in determining how to propagate a received frame. Use the search function of the Address Table screen to display information about the entries in the table.
...
===

FMI Netgear does also provide fine documentations for each product. Head to https://netgear.com/support start type in your product model number...

Back to the information provided:

Quick copy paste and does unveil this:

===

00:08:9B ICP Electronics Inc.

10:56:CA Peplink International Ltd.

--

3C:98:72 Sercomm Corporation.

68:5B:35 Apple, Inc.

F8:B4:6A Hewlett Packard

===

A few clicks show all you need to know.

Port 23 is connecting to another L2 device where a QNAP NAS and a some Peplink network device are connected, port 14 does connect to another L2 device where a Sercomm device, some Apple and HP units.

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@astirusty wrote:

I have never seen a router or switch show different MAC addresses assigned to same Interface (port).

---

Each switch or bridge does maintain an Address Table internally by port, by VLAN, .... Most simple devices resp. switch chips don't provide a monitoring access to the list - only managed cores do. If a switch does L3 routing, it does also have a dedicated MAC for each routing interface. And the device MAC addresses of routed IP addresses are becoming visible in the ARP table.(resp. an ARP cache). Time to use the Internet to read about about adapter vs. port vs. interface; and Address Table vs. ARP table.

[astirusty]

I know how to find manufacture of a device from MAC address. 

I also know the MAC address shown are not the MAC address(es) of GS724TPv2.  Which was of no importance for my need.

What I needed to know is what device by the MAC address was hooked into which connector in releation to listed ports G1-G24 (G25 & G26 are reserved for backbone).

Reason was I needed to remotely Disable correct G## port.  Disabling wrong G## port was going to leave GS724TPv2 unaccessible.  In this particular case it came down to disabling either G23 & G24.

One G2# was being used to connect to network router connecting to cellular modem.   The other G2# was one needing to be disabled.  To axe QNAP secondary Port.

From everything I read, including manual, the Address Table was supposed to show MAC address of device plugged into front pannel connector, and those connectors are related to G1-G24.

There should be a way to relate Device's MAC address to connector it is plugged into and relate coonector back to G1-G24 numbering.  Otherwise, you would simply be guessing when it comes to using Port Configuration and POE monitoring.