System-error LEDWhen 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. SeeChapter 5, “Solving problems,” on page 67 for additional information.Detailed troubleshooting information is in the Problem Determination andService Guide on the IBM Documentation CD.USB connectorsConnect USB devices to these connectors.CD or DVD eject buttonPress this button to release a CD from the CD drive or a DVD from theDVD drive.CD or DVD drive activity LEDWhen 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 diskdrive is in use.When the drive is removed, this LED also is visible on the SAS/SATAbackplane, next to the drive connector. The backplane is the printed circuitboard 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 associatedhard disk drive has failed.If an optional ServeRAID adapter is installed in the server and the LEDflashes slowly (one flash per second), the drive is being rebuilt. If the LEDflashes rapidly (three flashes per second), the adapter is identifying thedrive.When the drive is removed, this LED also is visible on the SAS/SATAbackplane, below the hot-swap hard disk drive activity LED.Chapter 3. Server controls, LEDs, and power 39