Enterasys Networks 9034313-07 About CoS-Based Flood Control

Configuring Policy Class of Service (CoS)

SecureStack C3 Configuration Guide 11-19

2.0 97 irl none

2.0 98 irl none

2.0 99 irl none

4. IntheCoSsettingstable,configureaCoSsettingforCoSindex1,whichhasapriorityof0.We

entertheIRLreference,createdinthepreviousstep.

C3(su)->set cos settings 0 irl-reference 1

C3(su)->show cos settings

CoS Index Priority ToS IRL

--------- ---------- ------- -----

0 0 * 1

1 1 * *

2 2 * *

3 3 * *

4 4 * *

5 5 * *

6 6 * *

7 7 * *

CoS‐basedfloodcontrolpreventsconfiguredportsfrombeingdisruptedbyatrafficstormbyrate‐

limitingspecifictypesofpacketsthroughthoseports.Whenfloodcontrolisenabledonaport,

incomingtrafficismonitoredoveronesecondintervals.Duringaninterval,theincomingtraffic

rateforeachconfiguredtraffictype(unicast,broadcast,multicast)iscomparedwiththe

configuredtrafficfloodcontrolrate,specifiedinpacketspersecond.

If,duringaonesecondinterval,theincomingtrafficofaconfiguredtypereachesthetrafficflood

controlrateconfiguredontheport,CoS‐basedfloodcontroldropsthetrafficuntiltheinterval

ends.Packets arethenallowedtoflowagainuntilthelimitisagainreached.

ThefollowingproceduredescribesthestepsandcommandsrequiredtoconfigureCoS‐based

floodcontrol.

Example

Thisexamplecreatesabroadcastratelimiter(index1.0)of5packetspersecondandassignsitto

portsge.1.2andge.2.2.

C3(su)->set cos state enable

C3(su)->set cos port-resource flood-ctrl 1.0 broadcast rate 5

C3(su)->set cos port-config flood-ctrl 1.0 ports ge.1.2;ge.2.2 append

Co

Note: CoS-based flood control does not require a policy license on SecureStack B3 switches or on

standalone D2 switches.

Procedure 11-2

Step Task Command(s)

1. Enable CoS. set cos state enable

2. Create a CoS flood control port resource, which

specifies flood control rate limiters that can be

mapped to specific ports.

set cos port-resource flood-ctrl

3. Assign the flood control resource to specific

ports. set cos port-config flood-ctrl