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MAC Address discovery issue

burleyman
Level 8
Level 8

I have a

Catalyst 4506 switch running IOS cat4000-i9s-mz12-25.EWA4.bin

The question I have is....

I have a Cisco Phone that is connected to an interface and a PC that is connected to the Phone. The Link speed should be 1000/full. When I run the command show mac-add dyn   I do not see any MAC Address entries for the phone or the PC on that port and it is only running at 100/full but I do have network connectivity for both the PC and Phone.. On other ports I can see the MAC address for both the Phone and PC. What could the issue be?

Thanks,

Mike

1 Accepted Solution

Accepted Solutions

Edison Ortiz
Hall of Fame
Hall of Fame

Auto/Auto at the IP Phone and switchport should negotiate to 1Gb/FD if both link partners support such speed/duplex setting.

If the negotiation did not occur and both are set to Auto/Auto, replace the cable at both ends.

Also, try connecting the phone to another switchport.

Regards

Edison

View solution in original post

4 Replies 4

Edison Ortiz
Hall of Fame
Hall of Fame

Auto/Auto at the IP Phone and switchport should negotiate to 1Gb/FD if both link partners support such speed/duplex setting.

If the negotiation did not occur and both are set to Auto/Auto, replace the cable at both ends.

Also, try connecting the phone to another switchport.

Regards

Edison

I am going through some of my post that I have resolved and rating them

and posting they were solved.

Thanks Edison for your help.

Mike

A thought about the lack of entries in show mac-addr dyn ... do you have port security on that port?  Secure addresses are regarded as static rather than dynamic.

Kevin Dorrell

Luxembourg

I did think about that but I do not have security on the ports. I did have them replace the cable even though they said they did already and that seemed to resolve the issue.

Mike

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