Configuring and Bringing Up a Stack

Use only QSFP transceivers and QSFP cables (separately purchased) to connect stacking ports as follows:

1Insert a QSFP cable in the bottom stacking port on the rightmost switch.

2Connect the upper stacking port on the next switch to the left.

3Continue connecting each switch to the next in this way until you reach the leftmost switch in the stack.

4On the leftmost switch, connect the bottom stacking port to the upper stacking port on the rightmost switch to create a loop.

NOTE: The resulting ring topology allows the entire stack to function as a single switch with resilient fail-over capabilities.

If you do not connect the leftmost switch to the rightmost switch (Step 4), the stack operates in a daisy-chain topology with less resiliency. Any failure in a non-edge stack unit causes a split stack.

NOTE: Although stacking is supported on 40GbE ports on the base module or a

2-Port 40GbE QSFP+ module, this section shows how to configure stacking only on the base-module ports (Figure 1-9).

To convert the 40GbE ports on the 2-Port QSFP+ module from their default 4x10GbE mode of operation to 40GbE mode to configure a stack, refer to "FlexIOTM Plug-in Modules" on page 7. After the converting the ports to 40GbE, you do not have to reload the switch because a switch reload is required as part of the stack configuration procedure.

After you attach the QSFP+ cables in a stack of MXL 10/40GbE Switches, to configure and bring up the stack, follow these steps:

1Connect the terminal to the console port on an MXL 10/40GbE Switch. Enter the following commands to access the CLI and configure the two 40GbE ports on the base module for stacking mode:

Password: *****

FTOS> enable FTOS# configure

FTOS(conf)# stack-unit 0 stack-group 0 FTOS(conf)# stack-unit 0 stack-group 1

Where stack-unit 0 defines the default stack-unit number in the initial configuration of a switch; stack-group 0 defines the stack group for the

Assembling a Switch Stack