Reference Guide

∙ When you run a D_Port test on the links between a FC16-64 port blade and a fixed-port switch or blade, run the test on one link
at time for short distance links. If you have 100-km links, you should start the test on other links only after the 100-km link test
is completed.
∙ In case of switch-to-Host Bus Adapter (HBA) or Access Gateway-to-HBA connections with Brocade HBA v3.2.3 or later,
Brocade recommends that D_Port tests be limited to a maximum of eight D_Ports at once. Otherwise, there is a possibility of
false alarms.
∙ If a remote SFP is not capable of running an optical loopback test or a QSFP is connected by means of a breakout cable to an
SFP, the test is skipped with the reason "No remote SFP or chip support" .
∙ During a dynamic D_Port configuration, when electrical or optical loopback testing is in progress and the switch is rebooted or
there is a failover, it is possible for the ports to end up in an unsynchronized state. To clear this condition, enter the
portDportTest --debug command on a D_Port, an E_Port, or both, as appropriate.
∙ Beginning with Fabric OS 8.0.1, on Gen 6 platforms it is possible to specify the number of transmitted frames and the duration
of the test for electrical and optical loopback tests.
NOTE
Long-duration optical loopback tests can be run on only one port at a time. Long-duration electrical loopback tests are
not supported.
∙ Refer to the following topics in this guide for additional specific information:
– "8 Gbps LWL and ELWL SFP transceiver limitations for D_Ports"
– "High Availability limitations and considerations for D_Ports"
– "Access Gateway limitations and considerations for D_Ports"
– "Host Bus Adapter limitations and considerations for D_Ports"
Access Gateway limitations and considerations for D_Ports
In addition to the items listed in "General limitations and considerations for D_Ports," you should keep in mind the following limitations
and considerations when using a D_Ports with Access Gateways:
∙ D_Ports on an Access Gateway are supported only when there is no mapping between F_Ports and N_Ports; this includes
static mapping and preferred port mapping. In addition, device (WWN) mapping is also not retained when a D_Port is used. If an
Access Gateway port to be tested is mapped, the port mapping (including static and preferred port mapping) must be removed
before the D_Port can be used. Refer to "Saving port mappings on an Access Gateway" in this chapter.
∙ Access Gateway supports D_Port dynamic mode only with HBAs. If the port on the connected HBA is configured as a D_Port,
the Access Gateway port automatically changes to D_Port mode. Once the Access Gateway port becomes a D_Port, the tests
are run automatically, and then when the HBA becomes a normal port, the Access Gateway port also switches to normal F_Port
mode. However, Access Gateway-to-Access Gateway and Access Gateway-to-switch port connections require static
configuration to become D_Ports.
∙ If a pre-Fabric OS 7.3.0 static D_Port is connected to a Fabric OS 7.3.0 and later port that is not a D_Port, and dynamic D_Port
mode is not enabled, credit loss may happen on the non-D_Port port.
∙ If a switch makes an on-demand D_Port request to a port on an Access Gateway running a version of Fabric OS earlier than
7.3.0 that is not a D_Port, the Access Gateway will disable the port. This restriction applies only to this combination of switch
and Access Gateway.
High Availability limitations and considerations for D_Ports
Consider the following High Availability (HA) limitations and considerations when using D_Ports:
Diagnostic Port
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