Cisco ICND2 – Verify configuration and connectivity using ping, traceroute, and telnet or SSH

Listed below is a quick list of tools that can be used to troubleshoot connectivity issue.


Ping can be used to verify connectivity between end devices. Note – A device such as a firewall may block the ICMP packet.


Shows routing paths from source to destination on a PC.


Telnet can be used to connect to a router/switch although data is sent in plain text


Same as Telnet, but data is encrypted.

Ipconfig /all

Display IP information that can be verified against network documentation. IP/Subnet mask/Default gateway information can be seen. DNS/WINS is also provided.

arp -a

Shows the MAC address table from a PC.

show ip arp

Shows the MAC address table from a router/switch.