cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
5988
Views
0
Helpful
6
Replies

Storm-control broadcast

jpl861
Level 4
Level 4

Hi,


We had an issue few days ago with one workstation sent 9000 multicat packets per second. All of our switches reached 100% CPU. We are using a 4506 running Sup2+. Now we wanted to put back the workstation into the network and see if this will reoccur since we tried to recreate the problem into a lab network but we failed.


  5 minute input rate 15164000 bits/sec, 9021 packets/sec

  5 minute output rate 9000 bits/sec, 18 packets/sec

     15256214 packets input, 3203804940 bytes, 0 no buffer

     Received 15256214 broadcasts (15256214 multicasts)


First, my question is, is storm-control broadcast work as inbound and not outbound of an interface?


Second, if i configure the storm-control broadcast, will it also suppress multicast traffic? I read an article before that a broadcast suppression also suppresses multicast but I'm not positive if I remember it right.


The IOS I am using (and I guess it's not supported by 4500 Sup2+) only supports broadcast suppression unlike the 3560s that can suppress unicast, broadcast and multicast.


Can anyone help me? Thanks.



John

6 Replies 6

Giuseppe Larosa
Hall of Fame
Hall of Fame

Hello John,

>> First, my question  is, is storm-control broadcast work as inbound and not outbound of an  interface?

yes,  storm control applies inbound.

>> Second, if i  configure the storm-control broadcast, will it also suppress multicast  traffic?

newer Sup6E has distinct multicast suppression storm control.

Other supervisors including II+ can add multicast suppression to broadcast suppression in 12.2(46)SG using

Switch(config-if)# storm-control 
broadcast
include multicast

see

http://www.cisco.com/en/US/docs/switches/lan/catalyst4500/12.2/46sg/configuration/guide/bcastsup.html#wp1052688

Hope to help

Giuseppe

Hi Giuseppe,

Are you sure that Storm control applies only inbound? I can see from the date of the post that it's not recent, sorry for awakening old threads. In the configuration guide and command reference I could not see any statements that say storm control is applied only to inbound traffic. So, what I decided to do was to test storm control on a actual switch. The conclusion was that it works for both inbound and outbound directions.

All my respect to you.

Thanks & regards,

Moath,

Ganesh Hariharan
VIP Alumni
VIP Alumni

Hi,


We had an issue few days ago with one workstation sent 9000 multicat packets per second. All of our switches reached 100% CPU. We are using a 4506 running Sup2+. Now we wanted to put back the workstation into the network and see if this will reoccur since we tried to recreate the problem into a lab network but we failed.


  5 minute input rate 15164000 bits/sec, 9021 packets/sec

  5 minute output rate 9000 bits/sec, 18 packets/sec

     15256214 packets input, 3203804940 bytes, 0 no buffer

     Received 15256214 broadcasts (15256214 multicasts)


First, my question is, is storm-control broadcast work as inbound and not outbound of an interface?


Second, if i configure the storm-control broadcast, will it also suppress multicast traffic? I read an article before that a broadcast suppression also suppresses multicast but I'm not positive if I remember it right.


The IOS I am using (and I guess it's not supported by 4500 Sup2+) only supports broadcast suppression unlike the 3560s that can suppress unicast, broadcast and multicast.


Can anyone help me? Thanks.



John

Hi John,

storm-control only works on INBOUND packets and for multicast control you need to configure separetlt on per interface basis (config-if)#storm-control multicast  level (#)[.(#)]

check out the below links for configuring strom control at switch level

http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2SXF/native/configuration/guide/storm.html

Hope to Help !!

Ganesh.H

Hello Ganesh,

John has a C4500 router not a C6500 and according to configuration guide the command you have suggested is not available unless you have a sup6E.

I've found that  note about the option include multicast that is specific of C4500.

To be noted from interface counters in original post that broadcast counter counts equal the multicast count.

Hope to help

Giuseppe

Hello Ganesh,

John has a C4500 router not a C6500 and according to configuration guide the command you have suggested is not available unless you have a sup6E.

I've found that  note about the option include multicast that is specific of C4500.

To be noted from interface counters in original post that broadcast counter counts equal the multicast count.

Hope to help

Giuseppe

Hi Giuseppe,

Oops that was my fault thanks for correcting the post

Ganesh.H

Hey thanks for the reply.


Yeah I saw that option too in some IOS but I cannot find the include multicast command on my IOS version. I also looked at out Sup4 engine and it isn't there either. So I need to look for that article where I read broadcast includes multicast. I don't know if I heard or read it right but I'll try to find out.

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Innovations in Cisco Full Stack Observability - A new webinar from Cisco