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● All stacked S5000 switches must run the same Dell Networking OS version. The minimum Dell Networking OS version
required is 9.1(1.0). To check the Dell Networking OS version that a switch is running, power on the switch and enter the
show version command. To download a Dell Networking OS version, go to http://support.dell.com.
● Stacking is not supported on switches enabled for virtual link trunking (VLT). To convert a stack unit to VLT operation, refer
to Reconfiguring Stacked Switches as VLT.
NOTE: Enable stacking on an S5000 switch by specifying one or more stack groups. A stack group can consist of four 10
GbE ports or one 40 GbE port. If you enable stacking on a group of four 10 GbE ports, all ports in the stack group are
enabled for stacking. To maximize throughput, Dell recommends using all four 10 GbE ports in the group for stacking. You
cannot use 10 GbE ports in a stack group which are enabled for stacking as data ports.
Cables for Stacked Switches
Before you attach cables to set up a stack of S5000 switches, ensure that the Dell Networking OS version running on each unit
is the same (the show version command) and that all switches are powered down.
Review the cabling requirements in Stack and Cable Requirements.
To connect 10 GbE and 40 GbE stacking ports, use normal port cables. For detailed cabling information, refer to the Dell
Networking S5000 Installation Guide.
NOTE: The S5000 does not require special stacking cables. The cables used to connect 10 GbE and 40 GbE data ports are
sufficient.
The following cabling procedure uses a ring topology. Follow the same steps to cable switches in any of the stacking topologies
shown in Supported Stacking Topologies. To attach the port cables, follow these steps:
1. Connect four 10 GbE ports in a stack group on stack unit 1 to four ports in a stack group on stack unit 2.
2. Connect four 10 GbE ports in another stack group on stack unit 2 to four ports in a stack group on stack unit 3.
3. Connect four 10 GbE ports in another stack group on stack unit 3 to four ports in a stack group on stack unit 4.
4. Connect four 10 GbE ports in another stack group on stack unit 4 to four ports in a stack group on stack unit 1.
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 last switch to the first 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.
Accessing the Stack CLI
To configure a stack, access the CLI through the stack master using the console port or a VTY line.
● Console access: You can access the stack through an attached console connection to the master switch to log in to the
CLI. Console access to the stack CLI is available on the master. The console port of the standby unit does not provide
management capability; only a limited number of commands are available.
● Remote access: You can access the stack CLI using the IP address of the dedicated management Ethernet interfaces on
the master switch through an SNMP, SSH, or Telnet connection.
Assigning a Priority to Stacked Switches
By default, each stack unit is assigned priority 0.
The switch with the highest priority number is elected master. The switch with the next highest priority number is elected
standby and takes over stack management if the master switch fails. The range of valid priority values is from 1 to 14.
To configure or revert assigning stacked switch priority, use the following commands.
1. Configure a stack so that the roles are assigned according to pre-determined priorities instead of using the highest MAC
addresses.
Global Configuration mode
stack-unit priority
2. Revert the management priority of a stack unit to the default value of 0.
Global Configuration mode
no stack-unit unit-number priority number
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Stacking