Service Manual

You can connect two units with two or more stacking cables in case of a stacking port or cable failure. Removal of only one of
the cables does not trigger a reset.
Important Points to Remember
• You can stack up to six systems.
• You cannot stack one system with other system types.
• You cannot enable stacking and virtual link trunking (VLT) simultaneously on the device. To convert a stacked unit to VLT,
see Reconfiguring Stacked Switches as VLT.
• When using the 40G ports, you can configure a single port as a stack port; each 40G port is a stack-group.
• All the ports in a stack-group are placed in stacking mode. Unused ports in that group cannot be used as data ports.
• Stacking on the device is accomplished through front-end user ports on the chassis.
• All stack units must have the same version of Dell Networking OS.
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 two 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 125.
1. Stack-group 0 (Ports 1, 2, 3, and 4) 2. Stack-group 1 (Ports 5, 6, 7, and 8)
Stacking 863