QoS for Cisco 2610 routers

[popokitgoo]

Hello, my service provider manages the leased line between our two office locations. We had asked them to limit FTP traffic between the two offices during times of congestion to 10% of available bandwidth. During our tests though, it seemed like their configuration was limiting FTP traffic to 10% all the time, instead of only during congestion. They have provided the following configuration for their QoS settings, and I was wondering if someone here could validate for me what it does?

policy-map limit_ftp

class ftp-active

bandwidth percent 10

class class-default

fair-queue

interface Virtual-Template25

ip unnumbered Loopback0

service-policy output limit_ftp

I have searched through IOS documentation, and I just can't find which line says to apply the policy only during congestion. Can someone help me identify that line? Much thanks for any help possible.

[tdrais]

This configuration does not limit ftp traffic it actually guarentees a minumum of 10% during congestion and allows ftp to compete with every one else for the rest

[hardiklodhia]

hi

i think the configuration is correct.the above configuration can make reserve min 10% of the ur bandwidth for ftp traffic in any conditiion.may be problem with ur testing.see this terms : available b/w and max-reserved-bandwidth.

The available bandwidth of an interface is calculated as:

Available_Bandwidth = (Configured_Bandwidth * max-reservedbandwidth/

100) - (LLQ - RTP - RSVP)

Where Configured_Bandwidth is the bandwidth value of the interface as specified

by the bandwidth command, and where max-reserved-bandwidth is the

configured max-reserved-bandwidth of the interface (defaults to 75%). This

reservable value is put into place to ensure that necessary network traffic (layer 2

keepalives, layer 3 routing) gets the service that it requires.

To see what the available bandwidth of an interface is issue the show queue

[interface] command.

may this help to test ur bandwidth again.

[popokitgoo]

Thanks so much for the explanation. I guess I did not understand the way QoS works. I was thinking of ways to limit FTP traffic, when the reality is that you guarantee a minimum. It makes perfect sense when you think about it from that angle. Thanks again for the replies!

[hardiklodhia]

Plz rate it if u found the correct answer.

rgrds,

hardik