Concept Guide

When connected to a QSFP or QSFP+ port on a 40 Gigabit adapter, QSA acts as an interface for the SFP or SFP+ cables. This interface
enables you to directly plug in an SFP or SFP+ cable originating at a 10 Gigabit Ethernet port on a switch or server.
You can use QSFP optical cables (without a QSA) to split a 40 Gigabit port on a switch or a server into four 10 Gigabit ports. To split the
ports, enable the fan-out mode.
Similarly, you can enable the fan-out mode to congure the QSFP port on a device to act as an SFP or SFP+ port. As the QSA enables a
QSFP or QSFP+ port to be used as an SFP or SFP+ port, Dell Networking OS does not immediately detect the QSA after you insert it into
a QSFP port cage.
After you insert an SFP or SFP+ cable into a QSA connected to a 40 Gigabit port, Dell Networking OS assumes that all the four fanned-out
10 Gigabit ports have plugged-in SFP or SFP+ optical cables. However, the link UP event happens only for the rst 10 Gigabit port and you
can use only that port for data transfer. As a result, only the rst fanned-out port is identied as the active 10 Gigabit port with a speed of
10G or 1G depending on whether you insert an SFP+ or SFP cable respectively.
NOTE: Although it is possible to congure the remaining three 10 Gigabit ports, the Link UP event does not occur for these ports
leaving the lanes unusable. Dell Networking OS perceives these ports to be in a Link Down state. You must not try to use these
remaining three 10 Gigabit ports for actual data transfer or for any other related congurations.
If you use an active optical cable (AOC), you can convert the QSFP+ port to a 10 Gigabit SFP+ port or 1 Gigabit SFP port. Use the speed
command to enable the required speed.
Important Points to Remember
• Before using the QSA to convert a 40 Gigabit Ethernet port to a 10 Gigabit SFP or SFP+ port, enable 40 G to 4*10 fan-out mode on
the device.
• When you insert a QSA into a 40 Gigabit port, you can use only the rst 10 Gigabit port in the fan-out mode to plug-in SFP or SFP+
cables. The remaining three 10 Gigabit ports are perceived to be in Link Down state and are unusable.
• You cannot use QSFP Optical cables on the same port where QSA is used.
• When you remove the QSA module alone from a 40 Gigabit port, without connecting any SFP or SFP+ cables; Dell Networking OS
does not generate any event. However, when you remove a QSA module that has SFP or SFP+ optical cables plugged in, Dell
Networking OS generates an SFP or SFP+ Removed event.
Example Scenarios
Consider the following scenarios:
• QSFP port 0 is connected to a QSA with SFP+ optical cables plugged in.
• QSFP port 4 is connected to a QSA with SFP optical cables plugged in.
• QSFP port 8 in fanned-out mode is plugged in with QSFP optical cables.
• QSFP port 12 in 40 G mode is plugged in with QSFP optical cables.
For these congurations, the following examples show the command output that the show interfaces tengigbitethernet
transceiver, show interfaces tengigbitethernet, and show inventory media commands displays:
Dell#show interfaces tengigabitethernet 1/40 transceiver
SFP+ 1 Serial ID Base Fields
SFP+ 1 Id = 0x0d
SFP+ 1 Ext Id = 0x00
SFP+ 1 Connector = 0x23
SFP+ 1 Transceiver Code = 0x08 0x00 0x00 0x00 0x00 0x00 0x00 0x00
SFP+ 1 Encoding = 0x00
………………
………………
Interfaces
445