Addendum

18
Stacking
This chapter describes the stacking enhancements and contains the following sections:
• Configuring the Uplink Speed of Interfaces as 40 Gigabit Ethernet
Configuring the Uplink Speed of Interfaces as 40 Gigabit
Ethernet
You can configure the I/O Aggregator switch in standalone, VLT, and stack modes to operate with an
uplink speed of 40 Gigabit Ethernet per second. Although the I/O Aggregator in programmable MUX
mode supports the functionality to configure any base module port or optional Flex IO QSFP+ module
port in native 40 GbE mode from Dell Networking OS Release 9.2.0.0, you can use the chassis
management controller (CMC) interface to access the switch and specify the 40 GbE QSFP+ module
ports to function in 40 GbE mode after the subsequent reload operation. By default, these QSFP+
modules function in 10GbE mode.
When you configure the native mode to be 40 GbE, the CMC sends a notification to the IOA to set the
default internal working of all of the ports to be 40 GbE after the reload of the switch is performed. After
you configure the native mode that denotes the uplink speed of the module ports to be 40 GbE, you
must enter the reboot command (not pressing the Reset button, which causes the factory default
settings to be applied when the device comes up online) from the CMC to cause the configuration of the
uplink speed to be effective.
This functionality to set the uplink speed is available from the CLI or the CMC interface when the I/O
Aggregator functions as a simple MUX or a VLT node with all of the uplink interfaces configured to be
member links in the same LAG bundle. You cannot configure the uplink speed to be set as 40 GbE by
default if the Aggregator functions in programmable MUX mode with mutiple uplink LAG interfaces or in
stacking mode because CMC is not involved with configuration of parameters when the Aggregator
operates in either of these modes with uplink interfaces being part of different LAG bundles.
After you restart the Aggregator, the 4-Port 10-Gigabit Ethernet modules or the 40GbE QSFP+ port that
is split into four 10GbE SFP+ ports cannot be configured to be part of the same uplink LAG bundle that is
set up with the uplink speed of 40 GbE. In such a condition, you can perform a hot-swap of the 4-port 10
Gbe Flex IO modules with a 2-port 40 GbE Flex IO module, which causes the module to become a part
of the LAG bundle that is set up with 40 GbE as the uplink speed without another reboot. The Aggregator
supports native 40 GbE mode for QSFP ports only in simple MUX mode and stacking mode of operation.
In stacking mode, the base 40 GbE module ports are used for stacking and native 40 gbE uplink speed is
enabled for only the QSFP+ ports on the optional 2-Port 40-Gigabit Ethernet QSFP+ FlexIO modules.
The following table describes the various speeds in different Aggregator modes. If a 4X10G SFP+ or a
4x10BASE-T module is plugged in and 40 Gbe mode is configured, it is in error-disabled state.
Table 9. Speeds in Different Aggregator Modes
Module Type Standalone
10G mode
Standalone
40G Mode
Stacking 10G
Mode
Stacking
40G mode
VLT 10G
Mode
VLT 40G
Mode
Base module 10G 40G 40G (HiGig) 40G 40G (Native) 40G
Stacking
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