Bandwidth control on Cisco 3750

[M Talha]

Dear All,

I am working on a scenario to limit the switch port on Cisco 3750 to have bandwidth of 8 mb/s up and down, currently this port is configured as trunk and i want to restrict vlan 10 (IP - 192.168.10.0/24) for 8 mb/s up and down. Need help in this regard.

Regards,

Talha

[Georg Pauwen]

Hello,

below is an example. You need to configure 'mls qos vlan-based' on all physical access and trunk ports which are allowing VLAN 10 traffic, in addition to applying the service policy to the VLAN interface (SVI).

mls qos
!
policy-map VLAN10_8MB
class class-default
police 8000000 8000 exceed-action drop
!
interface GigabitEthernet0/1
switchport trunk encapsulation dot1q
switchport mode trunk
mls qos vlan-based
!
interface FastEthernet0/1
switchport access vlan 10
switchport mode access
mls qos vlan-based
!
interface Vlan10
service-policy input VLAN10_8MB

[Deepak Kumar]

Hi,

You can archive your goal using the VLAN based configuration as below:

!

mls qos
!
policy-map V10_8MB
class class-default
police 8000000 8000 exceed-action drop
!
interface GigabitEthernet0/1
switchport trunk encapsulation dot1q
switchport mode trunk
mls qos vlan-based
!
interface FastEthernet0/12
switchport mode trunk

switchport trunk allowed VLAN 10,11,12
mls qos vlan-based
!
interface Vlan10
service-policy input V10_8MB

And here is the link for better understating the configuration on this switch:

https://www.cisco.com/c/en/us/support/docs/switches/catalyst-3750-series-switches/91862-cat3750-qos-config.html#cg23

Regards,

Deepak Kumar

[M Talha]

Dear Georg Pauwen,

I am getting this message when applying this to vlan interface. What should i do now ?

Switch(config)#int vlan 10
Switch(config-if)#service-policy input VLAN10_8MB

%QoS: policy-map with police action at parent level not supported on Vlan10 interface.

[Joseph W. Doherty]

As the other posters have shown, you can have an ingress policer. However, unclear whether you want to limit all traffic on VLAN 10 to 8 Mbps, or just VLAN 10 traffic on the trunk. If the former, the other posters show how. If the latter, believe you can police based on the VLAN's subnet applied to the trunk interface.

Unfortunately, you cannot (I recall?) have an egress policer. Depending on "where" your VLAN 10 traffic might go, i.e. if you can identify trunk bound destinations (or all trunk outbound traffic?) then you can police the VLAN 10 ingress.

[M Talha]

Dear Joseph,

I have configured an ISP vlan (layer 2) on my Cisco 3750-1 and trunked to other Cisco 3750-2 where i have Layer 4 Firewall which does all the NAT stuff and it is working like charm. now i have trunked this ISP vlan to another Cisco 3750-3 switch which resides in another business unit nearby. I want only this business unit not to exceed the speed of 8 mbps download and upload. Hope this clears up of what i exactly want to achieve.

[Joseph W. Doherty]

Well, again, your 3750 bandwidth controls are, an ingress policy policer, an interface port egress "shaper", and (which I didn't mention before) a QoS queue shaper.