Rate and give feedback:  Feedback Received. Thank You!

Rate and give feedback: 

X

This document helped resolve my issue

Yes No

Additional Comments

800 characters remaining

May we contact you if necessary?

Name:  

E-mail: 

Enter a valid Email ID

Need product assistance? Contact Juniper Support

Submit

This site is protected by hCaptcha and its Privacy Policy and Terms of Service apply.

English  

English

Example: Configuring Storm Control to Prevent Network Outages on EX Series Switches

Requirements

• One EX Series switch
• Junos OS Release 9.5 or later for EX Series switches

Overview and Topology

A storm is generated when messages are broadcast on a network and each message prompts a receiving node to respond by broadcasting its own messages on the network. This, in turn, prompts further responses, creating a snowball effect and resulting in a broadcast storm that can cause network outages.

You can use storm control to prevent broadcast storms by specifying the amount, also known as the storm control level, of broadcast traffic, multicast traffic, and unknown unicast traffic to be allowed on an interface. You specify the storm control level as the traffic rate in kilobits per second (Kbps) of the combined applicable traffic streams.

Note: On EX2200, EX3200, EX3300, and EX4200 switches—Storm control is not enabled for multicast traffic by default. The factory default configuration enables storm control on all interfaces at 80 percent of the available bandwidth used by the combined unknown unicast and broadcast traffic streams. On EX4500 and EX8200 switches—The factory default configuration enables storm control on all interfaces at 80 percent of the available bandwidth used by the combined broadcast, multicast, and unknown unicast traffic streams. On EX6200 switches—Storm control is not enabled for multicast traffic by default. The factory default configuration enables storm control on all interfaces at 80 percent of the available bandwidth used by the combined unknown unicast and broadcast traffic streams. Storm control can be disabled for each type of traffic individually.

Storm control monitors the level of applicable incoming traffic and compares it with the level that you specify. If the combined level of the applicable traffic exceeds the specified level, the switch drops packets for the controlled traffic types. As an alternative to having the switch drop packets, you can configure it to shut down interfaces or temporarily disable interfaces (see the action-shutdown statement or the port-error-disable statement) when the storm control level is exceeded.

The topology used in this example consists of one switch with 24 ports. The switch is connected to various network devices. This example shows how to configure the storm control level on interface ge-0/0/0 by setting the level to a traffic rate of 15,000 Kbps, based on the traffic rate of the combined applicable traffic streams. If the combined traffic exceeds this level, the switch drops packets for the controlled traffic types to prevent a network outage.

Configuration

CLI Quick Configuration

To quickly configure storm control based on the traffic rate in Kbps per second of the combined traffic streams, copy the following command and paste it into the switch terminal window:

Step-by-Step Procedure

1. Specify the traffic rate in Kbps per second of the combined traffic streams on a specific interface:
   [edit ethernet-switching-options]
user@switch# set storm-control interface ge-0/0/0 bandwidth 15000

Results

Display the results of the configuration:

Physical interface: ge-0/0/0, Enabled, Physical link is Up
  Interface index: 160, SNMP ifIndex: 503, Generation: 163
  Link-level type: Ethernet, MTU: 1514, Speed: Auto, Duplex: Auto,
  BPDU Error: None, MAC-REWRITE Error: None, Loopback: Disabled,
  Source filtering: Disabled, Flow control: Enabled, Auto-negotiation: Enabled,
  Remote fault: Online
  Device flags   : Present Running
  Interface flags: SNMP-Traps Internal: 0x0
  Link flags     : None
  CoS queues     : 8 supported, 8 maximum usable queues
  Hold-times     : Up 0 ms, Down 0 ms
  Current address: b0:c6:9a:67:90:84, Hardware address: b0:c6:9a:67:90:84
  Last flapped   : 2013-05-16 22:46:42 UTC (14w3d 03:13 ago)
  Statistics last cleared: Never
  Traffic statistics:
   Input  bytes  :            312742788                  512 bps
   Output bytes  :            245552919                    0 bps
   Input  packets:              3550009                    1 pps
   Output packets:              2622101                    0 pps
   IPv6 transit statistics:
    Input  bytes  :                   0
    Output bytes  :                   0
    Input  packets:                   0
    Output packets:                   0
  Egress queues: 8 supported, 4 in use
  Queue counters:       Queued packets  Transmitted packets      Dropped packets
    0 best-effort                    0                    1                    0
    1 assured-forw                   0                    0                    0
    5 expedited-fo                   0                    0                    0
    7 network-cont                   0              2622100                    0
  Queue number:         Mapped forwarding classes
    0                   best-effort
    1                   assured-forwarding
    5                   expedited-forwarding
    7                   network-control
  Active alarms  : None
  Active defects : None
  Interface transmit statistics: Disabled