Information Technology Reference
In-Depth Information
Table15-9 Show Interfaces Serial Field Descriptions (continued)
Field
Description
keepalive
Indicates whether keepalives are set.
Last input
Gives the number of hours, minutes, and seconds since
the last packet was successfully received by an interface.
Useful for knowing when a dead interface failed.
Last output
Gives the number of hours, minutes, and seconds since
the last packet was successfully transmitted by an
interface.
output hang
Gives the 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, the number of
days and hours is printed. If that field overflows, asterisks
are printed.
Output queue, drops
input queue, drops
Gives the 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 because the queue
is full.
5 minute input rate 5
minute output rate
Gives the average number of bits and packets transmitted
per second in the past 5 minutes.
The 5-minute input and output rates should be used only
as an approximation of traffic per second during a given
5-minute period. These rates are exponentially weighted
averages with a time constant of 5 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
Gives the total number of error-free packets received by
the system.
bytes
Gives the total number of bytes, including data and MAC
encapsulation, in the error-free packets received by the
system.
no buffer
Gives the 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.
Received...broadcasts
Gives the total number of broadcast or multicast packets
received by the interface.
runts
Gives the number of packets that are discarded because
they are smaller than the medium's minimum packet size.
Giants
Gives the number of packets that are discarded because
they exceed the medium's maximum packet size.
