How to limit ingress bandwidth on 2960s ?

[jjeong]

Thank you all your suggestions In advance, 

I would like to limit bandwidth on 2960s

so, it works for egress

srr-queue bandwidth limit 20 ( for 200mbps / giga int)

However, How to limit bandwidth for ingress on 2960s ?

Thank you.

[Francesco Molino]

Hi

You can use policy-map with police command and then apply it in your interface using service-policy input command.

You can also limit it per type of traffic. This is the same config as if you wanted to do qos config.

[jjeong]

Thank you so much for the suggestion Francesco,
Would you check it up for the config below ? (150mbps limit for both direction on giga int)

mls qos

access-list 199 permit ip any any

class-map match-all 150m
match access-group 199

policy-map 150-limit
class 150m
police 150000000 500000 exceed-action drop (don't know exactly calculate Bursting size, so I just took it as big as 500000)

interface GigabitEthernet1/0/31
srr-queue bandwidth limit 20 ( it works for egress I know)
service-policy input 150-limit



Egress is good, but can't handling Ingress.
burst size on my 2960s CLI is below

7F_SW3(config-pmap-c)#police 150000000 ?
<8000-1000000> Normal burst bytes

[Francesco Molino · Accepted solution]

The config looks like ok. You can use srr to limit egress or even use a policy-map as well in output direction.

To know more about burst, here is a good explanation: https://community.cisco.com/t5/switching/qos-burst-size/td-p/887525

For the formula, on Cisco doc, you'll be able to find it and it will be:
normal burst = configured rate * (1 byte)/(8 bits) * 1.5 seconds
extended burst = 2 * normal burst"

[jjeong]

I guess there's some bug or h/w problem on my switch.

anyway,

thank you for ur kind and specific reply Francesco.

Best regards.

[Francesco Molino]

Ok why did you say there's a bug?
Which switch are you using?

[jjeong]

Hello Francesco,
Thank you for your reply

I'm using 2960s with ISO (C2960S-UNIVERSALK9-M, Version 15.0(2)SE11, RELEASE SOFTWARE (fc3)

srr bandwidth limit works, but policing not.

srr works great without policing config.

however policing with srr combination didn't work together on my 2960s 

Can't be using together. 

and, 

using just only policing config ?

It doesn't work too.

just only srr limit is work.

[Francesco Molino]

Yes based on Cisco IOS Feature Navigator (https://cfn.cloudapps.cisco.com/ITDIT/CFN/) this switch hasn't any policing feature. Sorry about that.