Brocade Fabric OS Command Reference Manual Supporting Fabric OS v6.3.0 (53-1001337-01, July 2009)

Fabric OS Command Reference 641
53-1001337-01
portCmd
2
portCmd
Diagnoses intelligent ports.
Synopsis portcmd action [slot/]geport arguments optional_arguments
Description Use this command to invoke the end-to-end IP path performance (ipperf) characterization feature,
to ping or trace a route to a destination IP host from an intelligent GbE port, or to determine the
path characteristics between a local data source and a remote data sink.
When issued with the ipperf option, this command determines characteristics of the path to the
remote host. The output of --ipperf -S includes the following information:
Sampling frequency(s)
The interval specified with the -i option or the default (30 seconds).
Total Time(s) The time in seconds the command has been running since it was last issued.
BW The bandwidth measured in the last interval. Bandwidth is defined as the
total number of transmitted packets in bytes. BW represents what the FCIP
tunnel and the FC application register as throughput rather than the Ethernet
on-the-wire bytes.
WBW The current bandwidth weighted with a gain of 50%.
Loss(%) The number of TCP retransmits. This number averages the TCP retransmit
rate over the last display interval.
Delay(ms) The smoothed TCP round-trip time and variance estimate in milliseconds.
PMTU The path maximum transmission unit (MTU) represents the largest IP layer
datagram that can be transmitted over the end-to-end path without
fragmentation. This value is measured in bytes and includes the IP header
and payload. There is limited support for black hole PMTU detection. PTMUs
of decreasing size are sent: Jumbo PMTU (greater than 1500 bytes), 1500
bytes, and 1260 bytes, the minimum PMTU supported for FCIP tunnels. If the
1260 PMTU transmission fails, --ipperf terminates. There is no support for
aging. During black hole PMTU detection the BW, WBW, Loss and PMTU
values printed may not be accurate.
VLAN tagging ensures that test traffic traverses the same path as real FCIP traffic. A VLAN tag entry
must exist prior to issuing the --ping or --traceroute commands; this includes both the local and
remote sides. A VLAN Tag table entry is dynamically maintained by the ipperf application.
The following portcmd features are platform-specific:
Tperf Brocade FX-24 and 7800 only.
VLAN tagging Brocade FR4-18i and 7500 only.
ipperf Brocade FR4-18i and 7500 only.
IPv6 Brocade FR4-18i and 7500 only.
Notes End-to-end path characterization is not supported if there exists an IPSec-enabled tunnel using the
same source/local IP address.