cisco show mac address of connected device

Using the “mac-address sticky” option you will reduce efforts for managing mac address table on each port, while “mac-address maximum 2” will grant that no more than 2 MAC addresses can be applied on that port. When I do 'show mac-address-table vid 17' (these are Avaya switches) I see loads of MAC addresses on the VLAN but 'ahow arp' and 'show arp-table' show me no ip addresses. Once someone asks you to disable a device, you can match the IP address with its MAC address and disable the port you need.Īlso you can prevent users from “sniffing” the network by using the “protected port” feature given by Cisco Catalysts. I am looking on a site's core switch, with a view to removing some legacy VLANs, and I need to establish whether there are any devices on these VLANs.

I would suggest you to do a map of the layer 2 of your network using some simple tool (nmap with -sP option to do a ping sweep of the entire subnet) and gathering the whole information in an Excel file (or equivalent). The table shows not only the MAC addresses of connected devices, but also the port number they are associated with, and whether these entries are dynamic or permanent. Also, from a security point of view, a portscan action can be done using a spoofed IP address, so the information given is unreliable. To view the MAC address table on a Cisco 1900, issue the show mac-address-table command.

Since the switch is working at Layer 2 of the OSI model, you cannot associate an IP address on a port, but only a MAC address and the port it is connected.

Cisco show mac address of connected device