QOS Question

omahascooby1963 · ‎06-22-2009

Will the following confige cause data slowness, If I am reading it correct, looks like rdp will have a 5% cap on available bandwidth

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policy-map Voip1

class signal

bandwidth percent 8

class rtp

priority percent 80

class RDP

bandwidth percent 5

class class-default

fair-queue

policy-map Parent

class class-default

shape average 1000000

service-policy Voip1

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Edison Ortiz · ‎06-22-2009

It's not recommended to allocated 80% of the total bandwidth to priority traffic. The rule of thumb is 33% max as that much % can starve other traffic. It seems you are experiencing data starvation in your other classes.

QoS design needs to be understood by the person who is implementing it as there are plenty of variables on each design.

My best recommendation is to read the QoS SRND at this URL:

http://www.cisco.com/en/US/docs/solutions/Enterprise/WAN_and_MAN/QoS_SRND/QoS-SRND-Book.html

HTH,

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Edison.

Joseph W. Doherty · ‎06-22-2009

"Will the following confige cause data slowness, If I am reading it correct, looks like rdp will have a 5% cap on available bandwidth "

What do you consider "data slowness"?

RDP isn't capped at 5% with the bandwidth statement, the bandwidth statement guarantees a minimum of 5% (although I believe FQ in class-default can disrupt the guarantee on some platform's IOS). A class using just a bandwidth statement could obtain 100%.

The shaper value of 1,000,000, might be a cause of slowness if more bandwidth was actually available.

Florin Barhala · ‎06-23-2009

I don't get it; you re worried about the rest of the traffic, how well will it flow? or about the RDP sessions?

The good thing about bandwidth percent is that it's not FIXED; it's only guarantees that will not drop behind that percentage, but it can go higher if there's available BW, or can use 0, if there s no traffic of that type.