Create An S-Series Stack - Dell S4820T Configuration Manual

Create an S-Series Stack

Stacking is enabled on the device using the front end ports.
No configuration is allowed on front end ports used for stacking. Stacking can be made between 10G
ports of two units or 40G ports of two units. The stack links between the two units are grouped into a
single LAG.
Stack Group/Port Numbers
By default, each unit in Standalone mode is numbered stack-unit 0.
A maximum of eight 10G stack links or two 40G stack links can be made between two units in a stack.
The front end ports are divided into 16 stack groups, each with 40G of bandwidth. Stack groups 0
through 11 correspond to 10G stack groups with four ports each. Stack groups 12 to 15 are one 40G port
each.
The front end ports accommodate SFP, SFP+ and QSFP+.
• Ports are divided into 16 stack-groups (0 to 15) as shown in the following example. The stack groups
must be of a single speed - either all 10G or all 40G.
– stack-group 0 corresponds to ports 0-3, stack-group 1 corresponds to ports 4-7, so on through
stack-group 11.
– stack-group 12 corresponds to the 40G port 48, stack-group 13 corresponds to port 52, so on
through stack group 15.
Figure 119. Stack-Group Assignments
You can connect the units while they are powered down or up. Stacking ports are bi-directional.
When a unit is added to a stack, the management unit performs a system check on the new unit to
ensure the hardware type is compatible. A similar check is performed on the Dell Networking OS version.
If the stack is running Dell Networking OS version 8.3.12.0 and the new unit is running an earlier software
version, the new unit is put into a card problem state.
• If the unit is running Dell Networking OS version 8.3.10.x, it is upgraded to use the same Dell
Networking OS version as the stack, rebooted, and joined the stack.
• If the new unit is running an Dell Networking OS version prior to 8.3.10.x , the unit is put into a card
problem state, Dell Networking OS is not upgraded, and a syslog message is raised. The unit must be
upgraded to Dell Networking OS version 8.3.12.0 before you can proceed.
Syslog messages are generated by the management unit:
918
Stacking