36 Hardware DescriptionFigure 2-11. Power ConnectionWhen the device is connected to a different power source, the probability of failure in the event of apower outage decreases.Stack ID ButtonThe device front panel contains a Stack ID button used to manually select the Unit ID for the StackMaster and members.The Stack Master and members must be selected within 15 seconds of booting the device. If the StackMaster is not selected within 15 seconds, the device is booted in stand-alone mode. To select a Unit IDfor the device, reboot the device.The Stack Master receives the Unit ID of 1 or 2. If both Unit 1 and Unit 2 are present, the unit that is notelected functions as the Backup Master. Stack members receive a separate Unit ID (3-8). For example,if there are four units in a stack, the Master unit is either 1 or 2, the backup Master is either 1 or 2depending on the Unit ID of the Master unit, the third member is 3, and the fourth Stack member is 4.NOTE: The device does not automatically detect a stand-alone unit. If a Unit ID has already been selected, pressthe Stack ID button several times until no stacking LED is lit.
