01-04-2010 06:46 AM - edited 03-04-2019 07:06 AM
I am working at a client site that is an MPLS customer. The customer has an MPLS circuit that runs between their Main HQ and their Disaster Recovery site. I have been asked to analyze and report as well on the way the Qos Policy is written, and to provide any recommendations on how they can improve performance.
There is a statement within the Qos Policy as it exists at each end on the 3825 routers. The statement is called "shape average percent". Here is the policy from one side:
policy-map QoS
class COS2_traffic
set dscp af31
shape average percent 12
bandwidth percent 13
class COS3_traffic
set dscp af21
shape average percent 27
bandwidth percent 28
random detect dscp-based
class class-default
fair-queue
random detect
What does this statement mean and how is it different than the the "bandwidth percent" statement?
Thanks
Kevin
Solved! Go to Solution.
01-04-2010 07:59 AM
k-melton wrote:
I am working at a client site that is an MPLS customer. The customer has an MPLS circuit that runs between their Main HQ and their Disaster Recovery site. I have been asked to analyze and report as well on the way the Qos Policy is written, and to provide any recommendations on how they can improve performance.
There is a statement within the Qos Policy as it exists at each end on the 3825 routers. The statement is called "shape average percent". Here is the policy from one side:
policy-map QoS
class COS2_traffic
set dscp af31
shape average percent 12
bandwidth percent 13
class COS3_traffic
set dscp af21
shape average percent 27
bandwidth percent 28
random detect dscp-based
class class-default
fair-queue
random detect
What does this statement mean and how is it different than the the "bandwidth percent" statement?
Thanks
Kevin
Kevin
The bandwidth percent is a minimum bandwidth guarantee so if there is spare bandwidth that can be used from other classes it will be used.
The shape average percent is a maximum bandwidth guarantee so any packets above that bandwidth will be queued and sent when there is spare bandwidth within that class.
So they are doing 2 fundamentally different things.
Jon
01-04-2010 07:59 AM
k-melton wrote:
I am working at a client site that is an MPLS customer. The customer has an MPLS circuit that runs between their Main HQ and their Disaster Recovery site. I have been asked to analyze and report as well on the way the Qos Policy is written, and to provide any recommendations on how they can improve performance.
There is a statement within the Qos Policy as it exists at each end on the 3825 routers. The statement is called "shape average percent". Here is the policy from one side:
policy-map QoS
class COS2_traffic
set dscp af31
shape average percent 12
bandwidth percent 13
class COS3_traffic
set dscp af21
shape average percent 27
bandwidth percent 28
random detect dscp-based
class class-default
fair-queue
random detect
What does this statement mean and how is it different than the the "bandwidth percent" statement?
Thanks
Kevin
Kevin
The bandwidth percent is a minimum bandwidth guarantee so if there is spare bandwidth that can be used from other classes it will be used.
The shape average percent is a maximum bandwidth guarantee so any packets above that bandwidth will be queued and sent when there is spare bandwidth within that class.
So they are doing 2 fundamentally different things.
Jon
06-19-2012 08:28 PM
I have a query, in above example how these command workd together
shape average percent 27 << is this 27% of total BW available?
bandwidht percent 28
As per the above explanation it's look like Min BW allocated is 28% and Maximum 27%. Should it not be Min BW value lower than Max BW value?
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