On a Cisco Catalyst switch, you want to display the current MAC address forwarding or filtering table that shows which MAC addresses are associated with which ports. Which IOS command should you use to view this MAC address table?

Introduction / Context:
Cisco Catalyst switches maintain a MAC address table, also known as the forwarding or filter table, that maps MAC addresses to specific switch ports. This table is critical for efficient layer 2 forwarding. Network administrators routinely need to inspect this table to troubleshoot connectivity issues, verify where a device is connected, or confirm that learning is occurring as expected. The question asks which Cisco IOS command displays this MAC address table on a switch.

Given Data / Assumptions:

• The device is a Cisco switch running IOS with standard switch commands.
• You want to see which MAC addresses are associated with which interfaces and VLANs.
• You know that there is a specific show command used on switches for this purpose.
• Other commands such as show running-config or show interfaces provide different information.

Concept / Approach:
The MAC address table is a layer 2 construct. Cisco IOS on Catalyst switches provides the show mac address-table command to display this table. This command lists learned MAC addresses, the VLAN they belong to, and the associated port. Other similar sounding commands either do not exist or serve different functions. For example, show running-config displays configuration, not dynamic MAC learning. The key is to recall the exact syntax used by Cisco for this feature.

Step-by-Step Solution:
1. Recall that to view MAC address mappings on a Cisco switch, you use a show mac related command. 2. Consider the known standard command: show mac address-table. 3. Recognize that this command output lists MAC addresses, VLANs, and interfaces, matching exactly what the question asks for. 4. Evaluate the other options and see that they either refer to nonstandard commands or provide different types of information. 5. Conclude that show mac address-table is the correct IOS command to display the MAC forwarding table.

Verification / Alternative check:
If you have used Cisco switches, you likely have typed show mac address-table many times when tracing where a host is connected. On older software versions, a similar command was show mac-address-table, but modern syntax uses show mac address-table. The output clearly includes columns such as VLAN, MAC address, type, and ports, which confirms that it is the correct tool for this task.

Why Other Options Are Wrong:
Option a: show mac filter is not a standard command to display the main MAC address table on typical Cisco Catalyst switches. Option b: show running-config displays the device configuration, including interface settings and VLAN configuration, but not the dynamic MAC address table. Option d: show mac filter-table is not a standard IOS command and does not match Cisco documentation for viewing the MAC table. Option e: show interfaces mac is not a typical Cisco IOS command; show interfaces displays interface statistics but not the full MAC address table in tabular form.

Common Pitfalls:
Candidates sometimes confuse router and switch commands or assume that show running-config will reveal everything. Another pitfall is misremembering the dash or spacing in the command. On exams, command choices are often designed to look very similar, with small differences like hyphens or pluralization. Always recall that the correct switch command is written as show mac address-table with a space and not with hyphens or alternative words. Practicing on real or simulated Cisco devices helps embed the exact syntax into memory and avoids errors in both exam and real world troubleshooting situations.

Final Answer:
The correct IOS command is show mac address-table.