System information

Detailed Information on the show interfaces serial Command
Book Title
15-340
Sample Displays
The following is sample output from the show interfaces command for a synchronous serial
interface:
Router# show interfaces serial
Serial 0 is up, line protocol is up
Hardware is MCI Serial
Internet address is 150.136.190.203, subnet mask is 255.255.255.0
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, rely 255/255, load 1/255
Encapsulation HDLC, loopback not set, keepalive set (10 sec)
Last input 0:00:07, output 0:00:00, output hang never
Output queue 0/40, 0 drops; input queue 0/75, 0 drops
Five minute input rate 0 bits/sec, 0 packets/sec
Five minute output rate 0 bits/sec, 0 packets/sec
16263 packets input, 1347238 bytes, 0 no buffer
Received 13983 broadcasts, 0 runts, 0 giants
2 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 2 abort
1 carrier transitions
22146 packets output, 2383680 bytes, 0 underruns
0 output errors, 0 collisions, 2 interface resets, 0 restarts
Table 15-9 describes significant fields shown in the output.
Table 15-9 Show Interfaces Serial Field Descriptions
Field Description
Serial...is {up | down}
...is administratively down
Indicates whether the interface hardware is currently active (whether carrier
detect is present) or whether it has been taken down by an administrator.
line protocol
is
{up | down}
Indicates whether the software processes that handle the line protocol consider the
line usable (that is, whether keepalives are successful) or whether it has been
taken down by an administrator.
Hardware is Specifies the hardware type.
Internet address is Specifies the Internet address and subnet mask.
MTU Maximum transmission unit of the interface.
BW Indicates the value of the bandwidth parameter that has been configured for the
interface (in kilobits per second). The bandwidth parameter is used to compute
IGRP metrics only. If the interface is attached to a serial line with a line speed that
does not match the default (1536 or 1544 for T1 and 56 for a standard
synchronous serial line), use the bandwidth command to specify the correct line
speed for this serial line.
DLY Delay of the interface in microseconds.
rely Reliability of the interface as a fraction of 255 (255/255 is 100% reliability),
calculated as an exponential average over five minutes.
load Load on the interface as a fraction of 255 (255/255 is completely saturated),
calculated as an exponential average over five minutes.
Encapsulation Encapsulation method assigned to the interface.
loopback Indicates whether loopback is set.
keepalive Indicates whether keepalives are set.
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.
Last output Number of hours, minutes, and seconds since the last packet was successfully
transmitted by an interface.