Analyzing Network Performance Using RMON and Ethernet Statistics (Layer 2 & Layer 3)

Table 17-1.Interpreting Ethernet Interface Statistics (Continued)

Statistic

Indicates

Actions

 

 

 

Undersized

Count of packets with a valid CRC

Possible cause: Device or

Packets

that violate the minimum Ethernet

application creating non-compliant

 

packet size.

packets.

 

These malformed packets are most

Possible action: Use a network

 

often the result of software errors.

analyzer to identify the transceiver

 

 

which at the source of the problem.

 

 

If necessary, replace transceiver,

 

 

network adapter, or station.

 

 

 

Oversized

Count of packets with a valid CRC

Possible cause: Device or

Packets

that violate the maximum Ethernet

application creating non-compliant

 

packet size.

packets.

 

These malformed packets are most

Possible action: Use a network

 

often the result of software errors.

analyzer to identify the transceiver

 

 

which at the source of the problem.

 

 

If necessary, replace transceiver,

 

 

network adapter, or station.

 

 

 

Fragments

Fragments or runts result from

Possible causes:

 

normal collision activity in

•

Interference on network

 

Ethernet networks. A runt packet is

 

 

cabling.

 

an incomplete packet that is long

 

 

•

A Transceiver attached to the

 

enough to be detected by an

 

 

Repeater is generating Signal

 

Ethernet interface.

 

 

 

Quality Errors (SQE).

 

 

 

 

 

Possible actions (respectively):

 

 

•

Inspect cable runs to see if they

 

 

 

are too close to noisy devices,

 

 

 

and check for problems with

 

 

 

network devices.

 

 

•

Disable SQE on the Transceiver.

 

 

 

 

17-4

Cajun P550/P220 Switch Operation Guide