IBM System x3400 Type 7975 Installation Manual page 53

System-error LED
When this amber LED is lit, it indicates that a system error has occurred.
An LED on the system board might also be lit to help isolate the error. See
Chapter 5, "Solving problems," on page 67 for additional information.
Detailed troubleshooting information is in the Problem Determination and
Service Guide on the IBM Documentation CD.
USB connectors
Connect USB devices to these connectors.
CD or DVD eject button
Press this button to release a CD from the CD drive or a DVD from the
DVD drive.
CD or DVD drive activity LED
When this LED is lit, it indicates that the CD drive or DVD drive is in use.
Hot-swap hard disk drive activity LED (some models)
On some models, each hot-swap drive has a hard disk drive activity LED.
When this green LED is flashing, it indicates that the associated hard disk
drive is in use.
When the drive is removed, this LED also is visible on the SAS/SATA
backplane, next to the drive connector. The backplane is the printed circuit
board behind drive bays 4 through 11.
Hot-swap hard disk drive status LED (some models)
On some models, each hot-swap hard disk drive has an amber status LED.
If this amber status LED for a drive is lit, it indicates that the associated
hard disk drive has failed.
If an optional ServeRAID adapter is installed in the server and the LED
flashes slowly (one flash per second), the drive is being rebuilt. If the LED
flashes rapidly (three flashes per second), the adapter is identifying the
drive.
When the drive is removed, this LED also is visible on the SAS/SATA
backplane, below the hot-swap hard disk drive activity LED.
Chapter 3. Server controls, LEDs, and power
39