Tracking down a switch port by MAC address

AvgITGeekAvgITGeek Member Posts: 342 ■■■■□□□□□□
Hey all, I've been asked to track down a switch port by the MAC address of the connected device. It's a stack of 4 or 5 Cisco switches. I ran a show mac address-table and it returned a very long list. Is there any way to filter by the MAC address? If you need more info, I'll be able to access the stack tomorrow.



  • Options
    thomas_thomas_ Member Posts: 1,012 ■■■■■■■■□□
    show mac-address table address hhh.hhh.hhh
    show mac-address table | include [regex expression]
  • Options
    AvgITGeekAvgITGeek Member Posts: 342 ■■■■□□□□□□
    That did the trick! I was able to resolve my customers issue. Thanks much!

    EDIT for more info. Customer called with a complaint that a certain computer kept getting assigned an address in a different VLAN. It has been a long time since my CCNA studies but I was able to get them a listing of the VLANS on this stack. Decided to track down the port via MAC. First time was unsuccessful because they were now wireless. I was able to track down where their WiFi MAC was being learned via show etherchannel summary and then a show cdp neighbor.

    Once he plugged a non WiFi client into the network, I was able to find the port via show mac address-table address <MAC address> and when I did a show run interface gi2/0/23 it showed that port didn't have the VLAN access it needed. A quick config t interface gi2/0/23 and switchport access vlan 10 solved the issue.

    Thanks again to thomas_ as that was the piece I was missing. I should start studying for the CCNA again. I so much want to finish my 2012 MCSA though. So many exams, so little time.
Sign In or Register to comment.