Enterasys IRM2, Руководство пользователя

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Performance Graph 3-11
Statistics
To open the board-level Performance Graph window:
1. Click on the appropriate Board number to display the board menu.
2. Drag down to Performance Graph... and release. The board-level
Performance Graph window will appear.
To access the port-level Performance Graph window:
1. Click on the appropriate Port to display the port menu.
2. Drag down to Performance Graph... and release. The port-level Performance
Graph window will appear.
The Board and Port Performance Graph windows are the same as the
Performance Graph window displayed in
Figure 3-6 , except that they display
statistics applicable to the selected board or port. Each Performance Graph
window allows you to graph the following statistical variables:
Total Errors
Total Errors The total number of errors of any kind processed
by the device, board, or port.
Collisions The total number of collisions detected by the
device, board, or port.
CRC Errors The total number of packets with CRC (Cyclical
R
edundancy Check) detected by the device,
board, or port.
Runt Packets The number of runt packets detected by the
device, board, or port. A runt frame is one that is
less than the minimum Ethernet frame size of 64
bytes.
Giant Packets The number of giant packets detected by the
device, board, or port. A giant frame exceeds the
maximum Ethernet frame size of 1518 bytes
(excluding the preamble).
Algn. Errors The number of misaligned packets detected by
the device, board, or port. Misaligned packets
are those which contain a non-integral number
of bytes (that is, any unit of bits less than a byte);
they can result from a MAC layer packet
formation problem, or from a cabling problem
that is corrupting or losing data.
OOW Collns. The number of collisions out of the standard
collision window (51.2 µs) detected by the
device, board, or port. There are two conditions
which can cause this type of error to occur: either
the network’s physical length exceeds IEEE 802.3
specifications, or a node on the net is