Monitor Traffic through the Router - Baseline Operations Guide

To continue your diagnosis of a problem, display real-time statistics about the traffic passing through physical interfaces on the router.

Display Real-Time Statistics about All Interfaces on the Router

Purpose

To display real-time statistics about traffic passing through all interfaces on the router.

Action

To display real-time statistics about traffic passing through all interfaces on the router, use the following JUNOS command-line interface (CLI) operational mode command:

Sample Output

user@host> monitor interface traffic

host name                 Seconds: 15                  Time: 12:31:09
Interface    Link  Input packets        (pps)     Output packets        (pps)
 so-1/0/0    Down              0          (0)                  0          (0)
 so-1/1/0    Down              0          (0)                  0          (0)
 so-1/1/1    Down              0          (0)                  0          (0)
 so-1/1/2    Down              0          (0)                  0          (0)
 so-1/1/3    Down              0          (0)                  0          (0)
 t3-1/2/0    Down              0          (0)                  0          (0)
 t3-1/2/1    Down              0          (0)                  0          (0)
 t3-1/2/2    Down              0          (0)                  0          (0)
 t3-1/2/3    Down              0          (0)                  0          (0)
 so-2/0/0      Up          211035          (1)              36778          (0)
 so-2/0/1      Up         192753          (1)              36782          (0)
 so-2/0/2      Up         211020          (1)              36779          (0)
 so-2/0/3      Up         211029          (1)              36776          (0)
 so-2/1/0      Up         189378          (1)              36349          (0)
 so-2/1/1    Down              0          (0)              18747          (0)
 so-2/1/2    Down              0          (0)              16078          (0)
 so-2/1/3      Up              0          (0)              80338          (0)
 at-2/3/0      Up              0          (0)                  0          (0)
 at-2/3/1    Down              0          (0)                  0          (0)
Bytes=b, Clear=c, Delta=d, Packets=p, Quit=q or ESC, Rate=r, Up=^U, Down=^D

Meaning

The sample output displays traffic data for active interfaces and the amount that each field has changed since the command started or since the counters were cleared by using the C key. In this example, the monitor interface command has been running for 15 seconds since the command was issued or since the counters last returned to zero.

Display Real-Time Statistics about an Interface

Purpose

To display real-time statistics about traffic passing through an interface on the router.

Action

To display traffic passing through an interface on the router, use the following JUNOS CLI operational mode command:

Sample Output

user@R1> monitor interface so-0/0/1

Next='n', Quit='q' or ESC, Freeze='f', Thaw='t', Clear='c', Interface='i'
R1
Interface: so-0/0/1, Enabled, Link is Up
Encapsulation: PPP, Keepalives, Speed: OC3 Traffic statistics:
  Input bytes:                    5856541 (88 bps)
  Output bytes:                   6271468 (96 bps)
  Input packets:                   157629 (0 pps)
  Output packets:                  157024 (0 pps)
Encapsulation statistics:
  Input keepalives:                 42353
  Output keepalives:                42320
  LCP state: Opened
Error statistics:
  Input errors:                         0
  Input drops:                          0
  Input framing errors:                 0
  Input runts:                          0
  Input giants:                         0
  Policed discards:                     0
  L3 incompletes:                       0
  L2 channel errors:                    0
  L2 mismatch timeouts:                 0
  Carrier transitions:                  1
  Output errors:                        0
  Output drops:                         0
  Aged packets:                         0
Active alarms : None
Active defects: None
SONET error counts/seconds:
  LOS count                             1
  LOF count                             1
  SEF count                             1
  ES-S                                 77
  SES-S                                77
SONET statistics:
  BIP-B1                                0
  BIP-B2                                0
  REI-L                                 0
  BIP-B3                                0
  REI-P                                 0
Received SONET overhead:  F1        : 0x00  J0        : 0xZ

Meaning

The sample output shows the input and output packets for a particular SONET interface (so-0/0/1). The information can include common interface failures, such as SONET/SDH and T3 alarms, loopbacks detected, and increases in framing errors. For more information, see Track Error Conditions .

To control the output of the command while it is running, use the keys shown in Table 35.

Action	Key
Display information about the next interface. The monitor interface command scrolls through the physical or logical interfaces in the same order that they are displayed by the show interfaces terse command.	N
Display information about a different interface. The command prompts you for the name of a specific interface.	I
Freeze the display, halting the display of updated statistics.	F
Thaw the display, resuming the display of updated statistics.	T
Clear (zero) the current delta counters since monitor interface was started. It does not clear the accumulative counter.	C
Stop the monitor interface command.	Q

See the JUNOS System Basics and Services Command Reference for details on using match conditions with the monitor traffic command.