HP StorageWorks 2.140 Director Switch - Manual (Page 107)

Monitoring and managing the Director
105 Director Element Manager User Guide
Traffic Statistics with Receive and Transmit Values
This section describes the types of traffic statistics that display for a selected port:
■ Link Utilization % Rx and Link Utilization %Tx—There are separate
values for transmit (Tx) and receive (Rx) link utilization. The larger of these
two values displays on the bar graph.
The current link utilization for the port is expressed as a percentage. Each port
can transmit or receive data at 100 Megabytes (MB) per second if the port is
set to 1 Gig. If the port is set to 2 Gig, the port can transmit or receive data at
200 MB per second.This statistic shows the percentage of the maximum link
utilization currently being used. Link utilization is calculated over one-second
intervals. The maximum link utilization is 100%.
■ Frames Rx—The number of frames that the port has received.
■ Frames Tx—The number of frames that the port has transmitted.
■ Four byte words Rx—The number of words that the port has received.
■ Four byte words Tx—The number of words that the port has transmitted.
■ Flows rerouted from ISL—This displays if the optional Open Trunking
feature is installed or not. A value will only display if Open Trunking is
installed, the port is connected to an ISL, and flows were being rerouted. This
is the number of Fibre Channel traffic flows that were rerouted from this ISL
to another ISL due to congestion.
■ Flows rerouted to ISL—This displays if the optional Open Trunking feature
is installed or not. A value will only display if Open Trunking is installed, the
port is connected to an ISL, and flows were being rerouted. This will be the
number of Fibre Channel traffic flows that were rerouted to this ISL from
another ISL due to congestion.
Using Statistics for Troubleshooting
As a general rule, you should clear all counts after the system is stabilized.
When looking at the Performance View, roughly keep track of the time
interval when errors accumulate to judge the presence and severity of a
problem. Also, recognize that there is a link recovery hierarchy implemented
in Fibre Channel to handle some level of expected anomalies. In general, only
be concerned with error counts that increment very quickly.