6-168
Cisco Broadband Cable Command Reference Guide
OL-1581-07
Chapter 6 Cable CPE Commands
show interfaces cable-modem
Received broadcasts
Total number of broadcast or multicast packets received by the
interface.
runts
Number of packets discarded because they were smaller than
the medium’s minimum packet size. For example, any Ethernet
packet less than 64 bytes is considered a runt.
giants
Number of packets discarded because they were larger than the
medium’s maximum packet size. For example, any Ethernet
packet larger than 1518 bytes is considered a giant.
throttles
Number of times the receiver on the port was disabled, possibly
due to buffer or processor overload.
input errors
Includes runts, giants, no buffer, CRC, frame, overrun, and
ignored counts. Other input-related errors can also cause the
input errors count to be increased, and some datagrams may
have more than one error; therefore, this sum may not balance
with the sum of enumerated input error counts.
CRC
Number of cyclic redundancy checks (CRCs) generated by the
originating LAN station or far-end device that do not match the
checksum calculated from the data received. On a LAN, this
field usually indicates noise or transmission problems on the
LAN interface or the LAN bus itself. A high number of CRCs
is usually the result of collisions or a station sending bad data.
frame
Number of packets received incorrectly, having a CRC error
and a noninteger number of octets. On a LAN, this value is
usually the result of collisions or a malfunctioning Ethernet
device.
overrun
Number of times the receiver hardware was unable to hand
received data to a hardware buffer because the input rate
exceeded the receiver’s ability to handle the data.
ignored
Number of received packets ignored by the interface because
the interface hardware ran low on internal buffers. These
buffers are different from the system buffers mentioned
previously in the buffer description. Broadcast storms and bursts
of noise can cause the ignored count to be increased.
abort
Number of packets whose receipt was aborted.
packets output
Total number of messages sent by the system.
bytes
Total number of bytes, including data and MAC encapsulation,
sent by the system.
underruns
Number of times the transmitter has been running faster than
the router can handle.
output errors
Sum of all errors that prevented the final transmission of
datagrams out of the interface being examined. Note that this
may not balance with the sum of the enumerated output errors,
as some datagrams might have more than one error, and others
might have errors that do not fall into any of the specifically
tabulated categories.
Table 6-30 show interfaces cable-modem Field Descriptions (continued)
Field
Description
