McDATA Eclipse 2640 SAN, Administration And Configuration Manual

Page: 185 / 276

6
Monitoring SAN Router Operation and Connections
6-37
Viewing Statistics
Wrapping Counters
The SAN Router stores information in counters with a maximum
value of four billion. When this value is reached, the counter resets to
zero and the count begins again. When reporting statistics such as the
number of bytes received or transmitted, the counter can quickly fill
if the port is operating at full line rate. For a 1 Gbps FC port, this
counter can wrap in as little as 31 seconds. If the graph poll rate is set
at a period longer than this, the reported statistics can report incorrect
results. Be sure to set the graph’s polling period to accommodate the
rate of traffic across the monitored port.