Alcatel-Lucent Omni 6624 - Manual (Page 84)

Stack Overview Managing OmniSwitch 6600 Series Stacks
page 3-4 OmniSwitch 6600 Series Hardware Users Guide April 2004
Stacking Resiliency and Redundancy
The figure on page 3-3 shows a sample way to connect switches in a four-switch stack to ensure dual-
redundant connections. Except for the bottommost switch in the stack, Port 52 is connected to Port 51 on
the switch below it with a 30 centimeter stacking cable. On the bottommost switch Port 52 is connected to
Port 51 on the topmost switch in the stack with a 1 meter redundant stacking cable. If a stacking connec-
tion goes down data can still flow between all the switches in the stack. In addition, if a switch goes down
traffic can still flow between the switches that are still operating.
Note. See “Redundant Stack Connection” on page 3-13 for more information.
Slot Numbers within a Stack
By default, the slot number for OmniSwitch 6600 series switches is 8. In a stand-alone configuration you
would enter 8 when a Command Line Interface (CLI) command requires a slot number. For example, to
create VLAN 10 on port 1 on an OmniSwitch 6600 series with the default slot number you would enter
vlan 10 port default 8/1
In a stack, each switch must have a unique slot number, which is configured by the user. (See “Managing
Switches in a Stack” on page 3-16 for more information.) This slot number can be any whole number
between 1 and 8.
For example, if you have assigned slot number 2 to a switch you would enter
vlan 10 port default 2/1
The slot number for each switch is stored in the root /flash directory in the boot.slot.cfg file. This file must
exist on every switch in a stack or the stack will not be able to operate correctly. If you accidently delete
this file the switch will revert to the default slot number of 8 and will operate in standby mode. To restore
the slot number and rejoin the switch to the stack you must physically change the slot by following the
steps described in
Chapter 2, “OmniSwitch 6600 Series Chassis and Hardware Components,” and reboot
the switch.
Note. In a stack consisting of three or more switches a switch that had a primary or secondary CMM role
will rejoin the stack in an idle mode.