CoXeY said:
Afternoon all,
I'm not to hot on the Cisco side of things but I have a requirement to trottle the bandwidthing going through several ports of a Cisco 2950t switch. I believe this is possible but have no idea how to do it
Can anyone point me in the right direction on how i go about setting this up?
Cheers
Dan.
Hi Cisco 2950s support ingress policing, classification and marking at Layer3. To do it do the following.
To limit traffic going into a switchport.
1.> Create an extended access-list with the source and destination networks or host for which you wish to police traffic, eg
(access-list 101 permit ip 10.10.10.0 0.0.0.255 any) covers all hosts on the 10.10.10.0/24 subnet, going to any destination.
2.> Use cisco MQC to create a class map, to classify the traffic you wish to police
From global config issue the command "class-map match-all <name>"
This will then take you into c-map configuration, next use the match command and enter the number of the access list you created in step 1.
so it looks something like this.
(config)#class-map match-all test
(config-cmap)#match access-group 101
Next you need to create a policy map to specify what policy you wish to apply to the traffic, to create a policy map, do the follwing.
From global config, type the command "policy-map <test>"
then specify the class map you created in step 2 by entering "class <name"
Then you need to specify what to do with the traffic, in this case you want to rate limit traffic so "policing" will do this. use the police command to define what rate of bandwidth you wish to limit the traffic to, from 1-1000Mbps in 1Mb increments, you also need a burst size or it won't work.. see below example
policy-map test1
class test
police 1000000 8192 exceed-action drop
the 1000000 specifies 1Mbps the 8192 specifies the burst bytes, and the exceed action specifies what you do with traffic which exceeds the burst, so in this case traffic which is 1000000+8192kbps will be dropped.
Then you need to apply the policy map to an interface, 2950s support ingress queueing and scheduling only, to do this enter if-config mode and enter the following command:
service-policy input test1
This will then enable the policy map on the interface, because you can only limit traffic coming into an interface, it may be required to create a second class map and policy map for traffic going back to the host through the uplink port, using a reversed ACL. If you want to do ingress queueing and egress queueing on the same switch, you need at least a 3550.
First I'm gonna get another 2950 switch in so i can muck around without affecting live connectivity...
