1. 可以參考一下 LED 的解釋
   Color System Status
   Off: System is not powered on.
   Green: System is operating normally.
   Amber: System is receiving power but is not functioning properly.

Color RPS Status
Off: RPS is off or not properly connected.
Green: RPS is connected and ready to provide back-up power, if require
Flashing green: RPS is connected but is unavailable because it is providing power to another device (redundancy has been allocated to a neighboring device).
Amber: The RPS is in standby mode or in a fault condition. Press the Standby/Active button on the RPS, and the LED should turn green. If it does not, the RPS fan could have failed. Contact Cisco Systems.
Flashing amber: The internal power supply in a switch has failed, and the RPS is providing power to the switch (redundancy has been allocated to this device).

2. 有可能, 如果每次都是第二台出狀況, 那第二台嫌疑很大

3. 選 master 有五個順序如下
   (1).The switch that is currently the stack master
   (2).The switch with the highest stack member priority value
   (3).The switch that uses the non-default interface-level configuration
   (4).The switch with the higher Hardware/Software priority.
   (5).The switch with the longest system up-time
   (6).The switch with the lowest MAC address

我覺得沒有特別設定下, 如果是一台一台開機,最先開機那一台就是 master, 如果是一起開機, 那就是比lowest MAC address

4. member 的號碼是當加入 stack 時, 選擇目前 stack 當中"lowest available
   number in the stack"。