If the traffic rate is beloe the CIR, then there is no burst traffic. Normal
traffic below the CIR does not fall into the conform action or the exceed
action, because it is not bursting. This traffic is allowed through no
matter what. The conform action is only when the cir is exceeded but still
falls below the burst rate.
 
during your tests, was there enough traffic to exceed your cir? if not then
all of your tests would have the same result as the cir is never exceeded?
how did you generate traffic though the firewall to perform your tests?

  _____  

From: [email protected]
[mailto:[email protected]] On Behalf Of Dnyaneshwar
Gore
Sent: Friday, September 04, 2009 1:09 AM
To: Kingsley Charles
Cc: [email protected]
Subject: Re: [OSL | CCIE_Security] ASA, Ver 8.0, QoS - Police query


Hi Kings,
 
As per your below mail "The conform action is executed for packets within
the average rate and burst size." That means conform action will take place
for traffic within CIR and Burst rate or for normal traffic or for traffic
flowing as per expections. So if I set conform action as "drop" then its
should drop that normal traffic....isn't it? And this is wrong as I want to
allow normal traffic. I may be wrong but this is what I can figure out from
explanation.
 
Another point is that I have tested police coammnd with transmit and drop
action in lab but the result or output is same for all tests. No difference
in output.
 
Regards,
D.M.Gore


On Fri, Sep 4, 2009 at 10:53 AM, Kingsley Charles
<[email protected]> wrote:


Hi D.M.Gore

ASA supports single bucket system. Let's say the CIR is 9000 bps and burst
size is 1200 bytes. The following is configured as inbound for an Ethernet
interface.
 
police input 9000 1200 conform-action transmit exceed-action drop
 
 
The bucket size is 1200 bytes and that is maximum it can hold. The rate at
which tokens are added to the bucket is 9000 bps. If the packets exceed the
burst of 1200 bytes plus 9000 bps rate, the the packets are dropped. 
 
The conform action is executed for packets within the average rate and burst
size. 
 
The exceed action for a police command specifying traffic rate is executed
for packets within the average rate and excess burst size.
 
 
 
 
With regards
Kings
 
 
 
 
 
 
 

 
On Fri, Sep 4, 2009 at 9:36 AM, Dnyaneshwar Gore <[email protected]>
wrote:


Hi Stuart,
 
I found following explanation from Cisco command lookup tool:
 
Note   <http://tools.cisco.com/i/templates/blank.gif> :The police command
merely enforces the maximum speed and burst rate, forcing them to the
conforming rate value. It does not enforce the conform-action or the
exceed-action specification if these are present. 
 
So by this explanation it is clear that conform-action and exceed-action
does not take place even if they are specified in command. I was right.
 
Regards,
D.M.Gore


On Thu, Sep 3, 2009 at 3:48 PM, Dnyaneshwar Gore <[email protected]>
wrote:


Thansk for your explanation.
 
But I have some qeries as follows:

*        if conform action is transmit then it will allow traffic more than
CIR but less than Burst value.

But when I set conform action as transmit, I get same ping result i.e. 98 %
success rate as it was in when conform action is drop. There should be some
difrerence between two outputs.
 
I have attached results for different cases.
 
Also what should be the difference if I set exceed action as transmit.
 
Regards,
D.M.Gore
 
On Thu, Sep 3, 2009 at 3:10 PM, Stuart Hare <[email protected]>
wrote:


So this looks to be expected behaviour to me.
As soon as the 64k is reached your telling it to drop the traffic.
 
Exceeded action will never enter into this equation as you are dropping
conformed traffic, and theres no where else to go.
 
So basically your CIR sets your nominal rate of transfer, once you exceed
the CIR and enter the burst rate you are conforming, thus the conform action
comes into play. If you continue to use more than the burst rate you are
deemed to be exceeding and the exceed action steps in.
 
HTH
 
Stu


2009/9/3 Dnyaneshwar Gore <[email protected]>


PFA configuration and result. The diagrame is 
 
R1 (router) (136.1.121.13) -------------------(Inside/136.1.121.12
<http://136.1.121.12/> ) ASA (Outside/136.1.122.12 <http://136.1.122.12/> )
--------------------R2(router) (136.1.122.13)


On Thu, Sep 3, 2009 at 1:31 PM, Stuart Hare <[email protected]>
wrote:


Can you post the output and config?
 
What device are you doing this on?
 
Stu


2009/9/3 Dnyaneshwar Gore <[email protected]>


I am assuming that by using "police {inbound | outbound} CIR [Burst]
conform-action drop exceed-action drop" command, all traffic should drop as
conform action is drop. But it is not happening. I am pinging from inside
host to outside host with 1000 counts and 1500 size and result is successful
ping but with about 9 drops.
Same result with "police {inbound | outbound} CIR [Burst] conform-action
transmit exceed-action transmit" command.
 
By seeing this, conform and exceed action does not drop the packets. Then
what is their use?
 
Also why one will set exceed action as transmit? It should be drop as it is
crossing comitted rate.
 
Regards,
D.M.Gore


On Thu, Sep 3, 2009 at 12:58 PM, Stuart Hare <[email protected]>
wrote:


You say you found the output the same, but what about the result for each?
If you are using the same tests and cir/burst values then I would expect the
output from your show commands to be the same.
 
Of the top of my head (and it is still early in the morning), i cant see why
you would use 2 & 3.
2 is saying drop everything regardless, which you could have done with the
drop command instead of police.
3 is saying permit everything regardless.
 
For policing to be efficient and effective you need to set differing actions
for your conform and exceed, even if this is just marking the packets with
an ip precedence or dscp value, upon exceeding the rate.
 
Stu


2009/9/3 Dnyaneshwar Gore <[email protected]>


Hi ALL,
 
I am not able to understand the difference between following commands:
1. police {inbound | outbound} CIR [Burst]
2. police {inbound | outbound} CIR [Burst] conform-action drop exceed-action
drop
3. police {inbound | outbound} CIR [Burst] conform-action transmit
exceed-action transmit
 
I tested these commands in lab and found output same for all.
 
I think conform-action and exceed-action does not work even if they are
specified.
 
Request your opinion.
 
Regards,
D.M.Gore

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