Alcatel OS6850-P48 User Guide - Page 171

Managing OmniSwitch 6850/6850E Series Stacks Roles Within the Stack Using Saved Slot Information The saved slot number is the slot number the switch will assume following a reboot. This information is stored in a switch's boot.slot.cfg file; the switch reads its slot number assignment from this file at bootup and assumes the specified slot number within the stack. If switches in a stacked configuration have no preconfigured slot assignments, the slot number for each switch is dynamically assigned by the system software. Slot numbers can also be manually assigned by the user. For more information on manually assigning slot numbers, refer to "Manual Slot Number Assignment" on page 6-25. When a stack with preconfigured slot information is booted, it is not the lowest MAC address that determines the primary management module. Instead, the slot information stored in each switch's boot.slot.cfg is read by the system software and used in determining the primary. The switch with the lowest saved slot number becomes the primary management module. Note. Although, for ease-of-management purposes, it is recommended that slot numbers are assigned beginning with slot number 1, it is not a requirement. In other words, a stack of four switches can have slot assignments 3, 4, 5, and 6. However, it is important that each element in a stack is assigned a unique slot number. Do not assign duplicate slot numbers to elements in a stack. Otherwise, one or more switches will be forced into pass-through mode. For more information on pass-through mode, refer to page 6-14. For more information on using saved slot information to determine the primary switch in a stack, refer to the diagram below: Saved Slot 6 Saved Slot 5 Saved Slot 4 Saved Slot 3 1 Four switches are stacked; all switches are connected via stack- ing cables. The user configures each switch to have a unique saved slot number. When each saved slot number is configured, the information is automatically written to the boot.slot.cfg file located in the /flash directory of each switch. Reload 2 The user reloads all the elements in the stack either by issuing the reload all command or by physically powering off and then powering on all switches. Assumes Slot 6 Assumes Slot 5 Assumes Slot 4 Assumes Slot 3 3 Instead of assigning the primary management module based on the lowest MAC address, the system software reads the slot information from each switch's boot.slot.cfg file during the boot process. The switches in the stack come up using their assigned slot numbers. Slot 6 Slot 5 Slot 4 Primary: Slot 3 4 The switch with the lowest assigned slot number automatically assumes the primary management role. In this case, the switch assigned slot 3 has the lowest slot number in the stack and becomes the primary management module. Primary Management Module Selection Using Saved Slot Information OmniSwitch 6850/6850E Series Hardware Users Guide June 2011 page 6-9