One of the disk cartridges in my 3U Server has a blinking blue light.
This is normal. The disk cartridge with the blinking blue light contains the hot spare disk drive.
NOTE: If a disk cartridge is blinking amber, it does contain the hot spare disk drive, but it is not large enough to back up all the disk cartridges in the server. To remedy this problem, the blinking amber disk cartridge must be replaced with a disk cartridge containing a disk drive equivalent to the largest disk cartridge in the server.
