
Troubleshooting Routers
5-10
• wfCSMACDCerr
This shows the number of Ethernet controller chip collision detections.
This is meaningful only if the attached transceiver or hub device
implements an SQE (Signal Quality Error, also referred to as Ethernet
Heartbeat) Test as defined in ANSI/IEEE 802.3. SQE specifies the
periodic assertion of the transceiver’s collision detection circuitry during
down periods, and tests the integrity of the controller chip/transceiver
connection.
If the transceiver or hub device does not implement SQE, the value—0 or
1—is irrelevant.
If the transceiver or hub device implements a SQE:
– 0 indicates successful completion of the test.
– 1 indicates that the SQE test failed. In this case, CSMACD logs an
event noting SQE loss and verifies the integrity of the fuse. If the fuse
is the problem, CSMACD logs another event and disables service to
the line. If the fuse is OK, CSMACD retains service to the line.
• wfCSMACDTxClipFrames
This shows the number of frames clipped in the driver’s transmission
routine due to transmission congestion. Check for the type of data that is
transmitting. Determine whether a broadcast storm is disrupting the
network, or whether the traffic is too heavy for the segment.
• wfCSMACDRxReplenMisses
This shows the number of packet buffer misses while attempting to
replenish driver reception ring. Another entity is using all of the available
buffers. Go to “Memory or Buffer Problem” in Chapter 3.
• wfCSMACDUnAlignedFrames
This shows the number of non-word-aligned frames received for
transmission. A non-word-aligned frame means that the starting address
of the data in memory is not an even number. Some protocol
implementations in the router create non-word-aligned frames.
Komentáře k této Příručce