show ip interface brief

One line per interface: address, and both status columns.

interfaces

What it does

The two status columns mean different things and the pair is diagnostic. Status is layer 1 (is there signal), Protocol is layer 2 (is the line protocol up). 'up/down' means the cable is fine but keepalives, encapsulation or the far end are not.

Per vendor

PlatformCommand
Cisco IOSshow ip interface brief
Cisco NX-OSshow ip interface brief
Juniper JunOSshow interfaces terse
MikroTik RouterOS/ip address print
Aruba AOS-CXshow ip interface brief
Ubiquiti EdgeOSshow interfaces

Useful variations

  • Only interfaces that are upshow ip interface brief | include up
  • Exclude unassignedshow ip interface brief | exclude unassigned

Pitfalls

The misreadings that actually cost people time.

  • 'administratively down' is a `shutdown` in the config, not a physical fault.
  • up/down on a serial link is usually an encapsulation or clocking mismatch; on Ethernet, often a duplex or VLAN mismatch.
  • The address shown is the primary only — secondaries need `show ip interface`.

Related

show interfaces statusshow ip route