3Com DSA-3CV1100-02 Table17 Ethernet Traffic Counters (continued), Table18 HDLC Traffic Count Indicators

128 TROUBLESHOOTING
HDLC Traffic Counters The normal frame counters indicate HDLC traffic counters between the
CPE and the VCN AC. Some errored frame counters indicate fatal errors,
requiring replacement of the VCN AC, or handling of env ironmental
noise over the line.
Tab l e 18 presents normal counter indications and probable causes of
abnormal counter indications.
CRC error,
overrun,
Alignment
error, frame too
long, frame too
short
Containing receive
errors.
Zero Hardware failure:
VCN AC port,
Ethernet cable or
Ethernet switch
Table17 Ethernet Traffic Counters (continued)
Counter Counts the Frames Normal Count
Abnormal Count
Indicates
Table18 HDLC Traffic Count Indicators
Counter Counts the Frames Normal Count
Abnormal count
indicates
Tx frames Sent via the
telephone line
High No transmit data
Rx frames Received via
telephone line
High No receive data
Tx discarded The VCN AC was
unable to send
Low VCN AC software
limitation
Rx discarded The VCN AC (CO)
was unable to receive
Low, unless the
traffic is
bi-directional
VCN AC software
limitation
Overrun, Not
mine, DPLL error
Abort sequence,
Non aligned,
CRC error,
Frame too long
Containing Receive
errors
Low VCN AC hardware
failure if the number of
errors is growing.