System information

Troubleshooting Fiber Distributed Data Interface 5-77
show interfaces fddi
LER Link error rate.
Upstream | downstream
neighbor
Displays the canonical MAC address of outgoing upstream and downstream
neighbors. If the address is unknown, the value will be the FDDI unknown address
(0x00 00 f8 00 00 00).
Last input Number of hours, minutes, and seconds since the last packet was successfully
received by an interface. Useful for knowing when a dead interface failed.
output Number of hours, minutes, and seconds since the last packet was successfully
transmitted by an interface.
output hang Number of hours, minutes, and seconds (or never) since the interface was last reset
because of a transmission that took too long. When the number of hours in any of the
“last” fields exceeds 24 hours, the number of days and hours is printed. If that field
overflows, asterisks are printed.
Last clearing Time at which the counters that measure cumulative statistics (such as number of
bytes transmitted and received) shown in this report were last reset to zero. Note that
variables that might affect routing (for example, load and reliability) are not cleared
when the counters are cleared.
*** indicates the elapsed time is too large to be displayed. 0:00:00 indicates the
counters were cleared more than 231 ms (and less than 232 ms) ago.
Queueing strategy First-in, first-out queuing strategy (other queueing strategies you might see are
priority-list, custom-list, and weighted fair).
Output queue, input queue,
drops
Number of packets in output and input queues. Each number is followed by a slash,
the maximum size of the queue, and the number of packets dropped due to a full
queue.
5 minute input rate,
5 minute output rate
Average number of bits and packets transmitted per second in the past five minutes.
The five-minute input and output rates should be used only as an approximation of
traffic per second during a given five-minute period. These rates are exponentially
weighted averages with a time constant of five minutes. A period of four time
constants must pass before the average will be within 2 percent of the instantaneous
rate of a uniform stream of traffic over that period.
packets input Total number of error-free packets received by the system.
bytes Total number of bytes, including data and MAC encapsulation, in the error-free
packets received by the system.
no buffer Number of received packets discarded because there was no buffer space in the main
system. Compare with ignored count. Broadcast storms on Ethernet networks and
bursts of noise on serial lines are often responsible for no input buffer events.
broadcasts Total number of broadcast or multicast packets received by the interface.
runts Number of packets that are discarded because they are smaller than the medium’s
minimum packet size.
giants Number of packets that are discarded because they exceed the medium’s maximum
packet size.
CRC Cyclic redundancy checksum generated by the originating LAN station or far-end
device does not match the checksum calculated from the data received. On a LAN,
this 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
transmitting bad data.
frame Number of packets received incorrectly that have a CRC error and a noninteger
number of octets. On a LAN, this is usually the result of collisions or a
malfunctioning Ethernet device. On an FDDI LAN, this also can be the result of a
failing fiber (cracks) or a hardware malfunction.
Field Description