[c-nsp] Cisco 3400 port shaping message limitation

[Pavel Skovajsa]

Hello all,

I was in the middle of the configuration of ME-3400-24TS-A
(12.2(50)SE1) for port-shaping and run into interesting message:

censw(config-if)#!
censw(config-if)#!
censw(config-if)#interface FastEthernet0/12
censw(config-if)#service-policy output UNI-out-internet-1024kbps
censw(config-if)#service-policy input UNI-in-internet-1024kbps
censw(config-if)#!
censw(config-if)#!
censw(config-if)#interface FastEthernet0/22
censw(config-if)#service-policy output UNI-out-internet-1024kbps
censw(config-if)#service-policy input UNI-in-internet-1024kbps
censw(config-if)#!
censw(config-if)#!
censw(config-if)#interface FastEthernet0/5
censw(config-if)#service-policy output UNI-out-internet-1024kbps
QoS: Configuration failed.  The configured rate 1024000 bps is not
achievable in hw within 1% of configuration.
        Closest value(s) are: 1111111 bps, 1000000 bps
censw(config-if)#service-policy input UNI-in-internet-1024kbps
censw(config-if)#
censw(config-if)#service-policy output UNI-out-internet-1024kbps
QoS: Configuration failed.  The configured rate 1024000 bps is not
achievable in hw within 1% of configuration.
        Closest value(s) are: 1111111 bps, 1000000 bps
censw(config-if)#service-policy output UNI-out-internet-1024kbps
QoS: Configuration failed.  The configured rate 1024000 bps is not
achievable in hw within 1% of configuration.
        Closest value(s) are: 1111111 bps, 1000000 bps


The configuration of the policy-map is straightforward:
policy-map UNI-out-internet-1024kbps
 class class-default
    shape average 1024000
    queue-limit 272

The setting of the queue-limit is configured according to the
recommendation over here:
http://www.cisco.com/en/US/docs/switches/metro/me3400/software/release/12.2_52_se/configuration/guide/swqos.html#wp1497063

After little experimenting I figured out that when I change the
policy-map to this:
policy-map UNI-out-internet-1024kbps
 class class-default
    shape average 1000000
    queue-limit 272

It starts to work fine. The question still remains, what does this
error message actually mean, and why it got triggered when I applied
the policy to the 3rd interface in a row....

Can somebody shed some light into this?

Regards,
Pavel Skovajsa