Configuring Rate Limiting for BUM Traffic

If high rates of traffic are being received by the device on a given port of that VLAN, you can limit the number of BUM packets or bytes received each second on that port.
  1. Enter global configuration mode. 
    device# configure terminal
  2. Enter interface configuration mode. 
    device(config)# interface ethernet 1/1/1
  3. Enable BUM rate limits.
    The rate limit can be set in kilobits per second (kbps) or packets per second (pkts/sec). Specify the unit kbps to set the rate limit in kilobits per second. If the unit is not explicitly mentioned, the rate limit is measured in packets per second.
    1. Set a broadcast rate limit by port speed in kbps. 
      device(config-if-e40000-1/1/1)# broadcast limit 96 kbps
      To set the broadcast rate limit by packet per second, enter the following command.
      device(config-if-e40000-1/1/1)# broadcast limit 96
    2. Set an unknown unicast rate limit by port speed in kbps. 
      device(config-if-e40000-1/1/1)# unknown-unicast limit 96 kbps
      To set the unknown unicast rate limit by packet per second, enter the following command.
      device(config-if-e40000-1/1/1)# unknown-unicast limit 96
    3. Set a multicast rate limit by port speed in kbps. 
      device(config-if-e40000-1/1/1)# multicast limit 400 kbps
      To set the multicast rate limit by packet per second, enter the following command.
      device(config-if-e40000-1/1/1)# multicast limit 400
  4. Verify the configuration. 
    device(config-if-e40000-1/1/1)# show running-config interface | begin broadcast
 broadcast limit 96 kbps
 multicast limit 400 kbps
 unknown-unicast limit 96 kbps
...

    device#show running-config interface ethernet 1/1/2 | include limit
     broadcast limit 2000
     multicast limit 96
     unknown-unicast limit 96

Rate Limiting BUM Traffic Configuration Example

device# configure terminal
device(config)# interface ethernet 1/1/1
device(config-if-e40000-1/1/1)# broadcast limit 96 kbps
device(config-if-e40000-1/1/1)# unknown-unicast limit 96 kbps
device(config-if-e40000-1/1/1)# multicast limit 400
device(config-if-e40000-1/1/1)# show running-config interface | begin broadcast
Parent topic: Configuring Rate Limiting