I have a LAN of 3560's with several small consumer grade switches attached to them at various locations. All of the 3560 ports have auto-MDIX enabled. I am trying to determine if MDIX is actually in effect, i.e. if the port has the send & receive pairs flipped.
According to the 3560 command ref, the "show controller ethernet <interface name> phy" displays the operational status of auto-MDIX. That's great, but that command displays "Auto-MDIX: On" no matter what is connected to the port. In fact, it displays the same thing enven if NOTHING is connected to the port. For example:
0013: 0000 Interrupt Status Register : 0000 0000 0000 0000
0014: 9990 LED Configuration Register : 1001 1001 1001 0000
001B: EB00 Trim Enable Register : 1110 1011 0000 0000
Auto-MDIX : On [AdminState=1 Flags=0x00052248]
00-20-7B, 0F-0F, 01-00
Am I missing something here? I also found the "show interface <interface name> transceiver properties" command, which also displays the MDIX administrative and operational status. However, this command also always shows the operational status as "On". The display for the same port as above:
Switch#show int f0/2 trans prop
Diagnostic Monitoring is not implemented.
Name : Fa0/2
Administrative Speed: auto
Administrative Duplex: auto
Administrative Auto-MDIX: on
Administrative Power Inline: N/A
Operational Speed: auto
Operational Duplex: auto
Operational Auto-MDIX: on
Media Type: 10/100BaseTX
Anyone know how to see if MDIX is actually in effect?
As I said in the original post, the display Auto-MDIX: On does NOT mean that the cable is being crossed. The output of the command always displays that if auto-MDIX is administratively enabled. It displays that if another switch is connected to the port as you would expect it to. However, it also displays "auto-MDIX: On" if a normal host is connected to the port which is incorrect. It also displays that if NOTHING is connected to the port when it clearly is not flipping any pairs. I suspect that this is a bug in the code. I tried it with 12.2(25)SEE and 12.2(44)SE2 with the same results.
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