Administrator Guide

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 first 10 Gigabit port and you can use only that port for
data transfer. As a result, only the first fanned-out port is identified 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 configure 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 configurations.
NOTE: Trident2 chip sets do not work at 1G speeds with auto-negotiation enabled. As a result,
when you peer any device using SFP, the link does not come up if auto-negotiation is enabled.
Therefore, you must disable auto-negotiation on platforms that currently use Trident2 chip sets
(S6000 and Z9000). This limitation applies only when you convert QSFP to SFP using the QSA. This
constraint does not apply for QSFP to SFP+ conversions using the QSA.
Important Points to Remember
• Before using the QSA to convert a 40 Gigabit Ethernet port to a 10 Gigabit SFP or SFP+ port, you must
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 first 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 in a QSA setup.
• 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 a SFP or SFP+
Removed event.
• In the S6000 platform, you can use the QSA on any of the ports. However, the existing maximum fan-
out restrictions apply to the ports.
• The QSA module does not have a designated EEPROM. To recognize a QSA, Dell Networking OS
reads the EEPROM corresponding to a SFP+ or SFP module that is plugged into QSA. The access
location of this EEPROM is different from the EEPROM location of the QSFP+ module.
• The diagnostics application is capable of detecting insertion or removal of both the QSA as well as the
SFP+ or SFP optical cables plugged into the QSA. In addition, the diagnostic application is also
capable of reading the DDS and Vendor information from the EEPROM corresponding to SFP+ or SFP
optical cables. As a result, no separate detection of QSA is required.
Support for LM4 Optics
The newly supported LM4 optics are similar in behavior to the LR4 optics that are already supported.
However, in the output of show inventory media command, an LM4 optical module is denoted as
40G-LM4. Barring this exception, the functionality and behavior of LM4 optics is similar to LR4 optics.
Example Scenarios
Consider the following scenarios:
• QSFP port 0 is connected to a QSA with SFP+ optical cables plugged in.
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Interfaces