Managing the Switch34

LED patterns

Table 12 summarizes LED color and meaning.
The following indicates port link speeds:
•No light — 1Gbps
•Green — 2 Gbps
•Amber — 4 Gbps
•Shows green/amber — Invalid SFP
POST and boot specifications
POST is a system check that is performed each time the switch is powered on, rebooted, or reset.
During POST, the LEDs flash different colors. Any errors that occur during POST are listed in the error
log.
The Cisco MDS 9124e Switch performs POST when it is turned on or rebooted. Total boot time with
POST is approximately three minutes.

POST

The success or failure results of the diagnostic tests that run during POST can be monitored through
the error log or the command line interface.
POST includes the following steps:
•Preliminary POST diagnostics are run.
•Operating system is initialized.
•Hardware is initialized.
•Diagnostic tests are run on several functions, including circuitry, port functionality, memory,
statistics counters, and serialization.
Table 12 Port link status LED patterns
LED color Status of H ardware
Solid green Link is up.
Steady flashing green Link is up (beacon used to identify port).
Flashing green Link is up (traffic on port).
Solid amber Link is disabled by software.
Flashing amber A fault condition exists.
Off No link.