Just a quick one today. Ever so often, you need to check the status of a the power supplies in a switch or router. That information is nestled snugly in the show environment command. I'll give you the proper syntax and results for a few different platforms.

Example 1. Cisco 2611XM running Cisco IOS Software, C2600 Software (C2600-ADVIPSERVICESK9-M), Version 12.4(13a), RELEASE SOFTWARE (fc1)

SLAP1#show environment 
Power Supply:

        Redundant Power System is not present.


Board Temperature:

        normal.

Example 2. Cisco 7206XVR running Cisco IOS Software, 7200 Software (C7200-SPSERVICESK9-M), Version 12.4(15)T1, RELEASE SOFTWARE (fc2)

SLAP2#show environment all
Power Supplies:
        Power Supply 1 is AC Power Supply. Unit is on.
        Power Supply 2 is AC Power Supply. Unit is off.

Temperature readings:
        NPE Inlet        measured at 31C/87F
        NPE Outlet       measured at 36C/96F

Voltage readings:
        +3.45 V       measured at +3.45 V
        +5.15 V       measured at +5.21 V
        +12.15 V      measured at +12.24 V
        -11.95 V      measured at -11.81 V

Envm stats saved 3 time(s) since reload

Example 3. Cisco Catalyst 2960 running Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 12.2(37)SE1, RELEASE SOFTWARE (fc1)

SLAP3#show env power 
POWER is OK
SLAP3#show env all   
FAN is OK
TEMPERATURE is OK

POWER is OK
RPS is NOT PRESENT

A quick note on the output of the Catalyst 2960. show env power only shows the status of the built-in power supply. If you are using an RPS on this system, you need to use show env all to get the RPS status, as well.