storm-control config under the interface

[jigojar]

Hi genius,

 if i am configuring the storm-control(multicast,broadcast) under the interface then data traffic will be blocked more than limit which i configured.

[balaji.bandi]

As per i know no if you configure only broadcast / multicast. if they hit on the Limit the port go in to error disable.

[jigojar]

Hi Balaji,

 My question is when storm-control is configured then during the violation will it block the data traffic or only control-plane traffic?

[balaji.bandi]

When it triggers based on the decision, most case the interface go in error disabled mode, since you configure strom control on the interface. (due to viloation)

if you using CoPP that is different  - what is the device model and IOS Code running.

[jigojar]

HI,

 We have only two optics when the threshold crosses.

1. shutdown

2. generating the trap

My question is when the threshold is will be decided based on data traffic or control-plane traffic

[balaji.bandi]

what is the config on the interface - can you post show run inter gi x/x

in general look at the document :

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst6500/ios/12-2SX/configuration/guide/book/storm.html

[jigojar]

HI,

Pls find the interface config

interface TenGigabitEthernet1/8
switchport trunk allowed vlan 100-200
switchport mode trunk
load-interval 30
storm-control broadcast level 2.00
storm-control action shutdown

[balaji.bandi]

storm-control broadcast level 2.00
storm-control action shutdown

This is your config, as per technically there is no guide lines how this need to be configured, this all depends on your network, how lasrge your broadcast traffic in the network, this is depends on network size and where this switch is located in the path.

this required some understand, by looking at the stastics and setup, the port not going to shutdown due to data traffic hit ratios. (i do see myslef in lasrge exit point where the port-channel with large traffic, the port go in shutdown when we connecting device to other network).

check this thread what TAC suggesting :

https://community.cisco.com/t5/switching/storm-control-thresholds/td-p/707264

https://community.cisco.com/t5/switching/storm-control-guidelines-and-best-practices/td-p/1279966

[Giuseppe Larosa]

Hello @jigojar ,

note that

storm-control action shutdown is optional in most implementations I have seen this feature not used.

To answer to your question the type of traffic broadcast is measured in 1 seconds time intervals, if the threshold is crossed all traffic of that type is dropped .

if in next time intervals the broadcast traffic is again below the level the broadcast traffic is allowed.

The storm-control affects both user data traffic and control plane traffic.

From the link provided by BB there are notes abour storm control  if using storm control for multicast traffic:

• Except for BPDUs, traffic storm control does not differentiate between control traffic and data traffic.
• When multicast suppression is enabled, traffic storm control suppresses BPDUs when the multicast suppression threshold is exceeded on these modules:

–

WS-X6748-SFP

–

WS-X6724-SFP

–

WS-X6748-GE-TX

–

WS-X6748-GE-TX

–

WS-X6704-10GE

–

WS-SUP32-GE-3B

–

WS-SUP32-10GE-3B

–

WS-X6708-10G

When multicast suppression is enabled on the listed modules, do not configure traffic storm control on STP-protected ports that need to receive BPDUs.

Hope to help

Giuseppe