show ip interface brief
One-line per interface: IP, admin status, line protocol. The single most useful verification command.
Example
R1# sh ip int brSample output
Interface IP-Address OK? Method Status Protocol
Gi0/0 10.0.0.1 YES manual up up
Gi0/1 10.0.1.1 YES manual up up
Se0/0/0 unassigned YES manual administratively down down
Se0/0/1 unassigned YES manual administratively down downCaptured from the NetForge-AI simulator running a real topology.
Status 'administratively down' = the port is shut (a new router's ports all are); 'down' = enabled but no signal (no cable, or the far end is shut); 'up' = signal. Protocol = line protocol, up only with a working cable and both ends enabled.
Don't just read it — type show ip interface brief in a real network simulator in your browser and watch it take effect. No install, no account needed to start.
Frequently asked
What does the "show ip interface brief" command do?
One-line per interface: IP, admin status, line protocol. The single most useful verification command.
What's the common gotcha with "show ip interface brief"?
Status 'administratively down' = the port is shut (a new router's ports all are); 'down' = enabled but no signal (no cable, or the far end is shut); 'up' = signal. Protocol = line protocol, up only with a working cable and both ends enabled.
Example of "show ip interface brief"
R1# sh ip int br