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To connect stacking ports, use only SFP+ transceivers, SFP+ cables and BaseT and its supported cables (separately
purchased). For example:
1. Insert a cable in port 9 on the first aggregator.
2. Connect the cable to port 10 on the next aggregator.
3. Continue this pattern on up to 6 aggregators.
4. Connect a cable from port 9 on the last aggregator to port 10 on the first aggregator. This creates a ring topology.
NOTE: The resulting topology allows the stack to function as a single switch with resilient failover capabilities.
Accessing the CLI
To configure a stack, you must access the stack master in one of the following ways.
● For remote out-of-band management (OOB), enter the OOB management interface IP address into a Telnet or secure shell
(SSH) client and log in to the switch using the user ID and password to access the CLI.
● For local management, use the attached console connection to the master switch to log in to the CLI. Console access to the
stack CLI is available on the master only.
● For remote in-band management from a network management station, enter the virtual local area network (VLAN) IP
address of the management port and log in to the switch to access the CLI.
Configuring and Bringing Up a Stack
After you attach the cables in a stack of Aggregators, perform the following steps to configure and bring up the stack:
1. Set up a connection to the CLI on an Aggregator as described in Accessing the CLI.
2. Connect the terminal to the console port on an Aggregator. Enter the following commands to access the CLI and configure
the base module ports for stacking mode:
Login: username
Password: *****
Dell> enable
Dell# configure
Dell(conf)# stack-unit 0 iom-mode stack
Where stack-unit 0 defines the default stack-unit number in the initial configuration of a switch.
3. Save the stacking configuration on the SFP+ or 10G Base-T ports:
Dell# write memory
4. Reboot the Aggregator by entering the reload command in EXEC Privilege mode:
Dell# reload
Repeat the above steps on each Aggregator in the stack by entering the stackunit 0 iom-mode stack command and
saving the configuration.
If the stacked switches all reboot at approximately the same time, the Aggregator with the highest MAC address is
automatically elected as the master switch. The Aggregator with the next highest MAC address is elected as the standby
master.
NOTE:
You can ensure that a stacked switch becomes the master by rebooting the switch first, and waiting for it to come
up before rebooting the second switch in the stack. It is recommended to have the boot image for the stack units via boot
from flash.
The Status LED on the Aggregator that is elected as the master switch is blue. Perform VLAN and other software configuration
for the stack by connecting to the console port on the master unit. To determine which switch is the stack master, enter the
show system command at the terminal.
To remove an Aggregator from the stack, enter the stack-unit 0 iom-mode standalone command in Global
configuration mode, save the configuration and reload the Aggregator for the change to take effect.
In stack mode, all VLAN membership are removed and the port is assigned only to the default VLAN1. You must configure
additional VLAN membership, as required.
Stacking
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