The stack ID uniquely identifies the stack; all members of the stack have the same stack ID. A switch is considered to be a part of a stack When it has the same stack ID as the stack commander. The stack ID is valid only when hpStackSwitchAdminStatus is true (1). This value is set by the first elected commander and stays with the stack until the user sets the hpStackSwitchAdminStatus to 'false (2)' or when hpStackSetStacking is set to 'true (1)' in an inactive fragment.