Inspect router hardware and interfaces

Start with two Cisco routers connected by a single Ethernet link.

Check the hardware model with show inventory and the software with show version.

On the first router, label the port, configure an address, and bring it up.

Set the IP maximum transmission unit and check the value on the interface.

Check that the peer router replies before you change the port state.

Shut down the local interface and check that the peer is unreachable.

Bring the interface up again and verify that traffic recovers.

An unsupported port is rejected and does not appear in the interface list.