Reference Guide

Stacking Installation Tasks
The following are the stacking installation tasks.
● Create a Stack
● Add Units to an Existing Stack
● Split a Stack
Create a 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 1.
A maximum of eight 10G stack links or four 40G stack links can be made between two units in a stack. The front end ports are
divided into 18 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 17 are one 40G port each.
The front end ports accommodate SFP, SFP+ and QSFP+.
● Ports are divided into 18 stack-groups (0 to 17) 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 1-4, stack-group 1 corresponds to ports 5-8, so on through stack-group 11.
○ stack-group 12 corresponds to the 40G port 49, stack-group 13 corresponds to port 50, so on through stack group 17.
Figure 127. Stack-Group Assignments
1.
Stack-group 0 (Ports 1, 2, 3, and 4) 2. Stack-group 1 (Ports 5, 6, 7, and 8)
3. Stack-group 2 (Ports 9, 10, 11, and 12) 4. Stack-group 3 (Ports 13, 14, 15, and 16)
5. Stack-group 12 (Port 49) 6. Stack-group 14 (Port 51)
7. Stack-group 16 (Port 53) 8. Stack-group 17 (Port 54)
9. Stack-group 15 (Port 52) 10. Stack-group 13 (Port 50)
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 EMC Networking OS version. If the stack is running Dell EMC 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 EMC Networking OS version 8.3.10.x, it is upgraded to use the same Dell EMC Networking OS
version as the stack, rebooted, and joined the stack.
● If the new unit is running an Dell EMC Networking OS version prior to 8.3.10.x , the unit is put into a card problem state, Dell
EMC Networking OS is not upgraded, and a syslog message is raised. The unit must be upgraded to Dell EMC Networking
OS version 8.3.12.0 before you can proceed.
Syslog messages are generated by the management unit:
● before the management unit downloads its Dell EMC Networking OS version 8.3.12.0 or later to the new unit. The syslog
includes the unit number, previous version, and version being downloaded.
● when the firmware synchronization is complete.
Stacking
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