Rate-limit command in 851 router

[gururajan]

we have configured rate-limit command in 851 router for controlling the inbound and outbound traffic. It is configured as,

interface FastEthernet4.102

encapsulation dot1Q 102

ip address **** ****

rate-limit input 1024000 128000 128000 conform-action continue exceed-action drop

rate-limit output 1024000 128000 128000 conform-action continue exceed-action drop

& cef is also enabled globally

But we can see more traffic than the configured rate using our SNMP reporting tool. We dont see any drops in the interface using the below,

sh interface FastEthernet4.102 rate-limit

FastEthernet4.102 ## 1Mbps(1:1) ## Annamalai Capital Services Pvt Ltd ##

Input

matches: all traffic

params: 1024000 bps, 128000 limit, 128000 extended limit

conformed 9 packets, 685 bytes; action: continue

exceeded 0 packets, 0 bytes; action: drop

last packet: 257706484ms ago, current burst: 0 bytes

last cleared 2d23h ago, conformed 0 bps, exceeded 0 bps

Output

matches: all traffic

params: 1024000 bps, 128000 limit, 128000 extended limit

conformed 0 packets, 0 bytes; action: continue

exceeded 0 packets, 0 bytes; action: drop

last packet: 257855364ms ago, current burst: 0 bytes

last cleared 2d23h ago, conformed 0 bps, exceeded 0 bps

Please clarify whether rate limiting is supported here.

Regards,

Guru

[Giuseppe Larosa]

Hello Guru,

clearly the feature is not working.

It might be bypassed by CEF

You can :

try to disable CEF on the main interface and the subif

OR

keep CEF enabled and

try to use Modular QoS using a service-policy with the rate command inside

policy-map police-all-in

class class-default

police 1024000

policy-map police-all-out

class class-default

police 1024000

int f4.102

service-policy input police-all-in

service-policy output police-all-out

Hope to help

Giuseppe

[gururajan]

Thanks for your reply.

I will check the same after disabling cef & update u.

But Policy-map command is not available in 851 router & IOS is

"flash:c850-advsecurityk9-mz.124-15.T6.bin"

Regards,

Guru

[gururajan]

Hi,

After disabling cef feature, rate-limit started working.

Thanks a lot for your input.

Regards,

Guru

[suryakant.chavan]

hi guru,

Please Explain use of these three values (1024000, 128000, 128000)in command,

rate-limit input 1024000 128000 128000 conform-action continue exceed-action drop

Regards,

Suryakant