Cisco 7609- Cannot use LLQ (priority command on the GE port)

Unanswered Question
Jan 28th, 2008

I cannot configure LLQ (priority command on the GE port) for voice traffic.

error is shown below:-

policy-map voice_internet

class internet

police cir 150000000 bc 4687500 be 4687500 conform-action transmit exceed-action drop

class voice


police cir 7000000 bc 218750 be 218750 conform-action transmit exceed-action drop

host(config)#int gi4/5

host(config-if)#service-policy ou

host(config-if)#service-policy output voice_internet

priority command is not supported in output direction for this interface

Configuration failed on:



Is there any commands or solution to configure QOS for converged voice traffic in my router? Can I use "mls qos" command

Thanks in advance

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 3.7 (3 ratings)
Paolo Bevilacqua Mon, 01/28/2008 - 02:40

Hi, sorry I don't know the exact answer to your question, but unless your gigabit becomes congested for like half a second, (very unlikely), you don't need any any qos on such high speed interfaces.

noxkrugger Mon, 01/28/2008 - 05:26

I need to prioritize the voice traffic. Is there any Qos method I can do maybe MLS QOS, or MQC ? Actually,what is the purpose of mls qos?

the modules are WS-X6148A-GE-TX Catalyst 6500 48-Port 10/100/1000 GE Mod.,RJ-45.

jmcmasters Wed, 04/30/2008 - 13:19

If this is for the Egress Queue and you can assign the QOS based on mappings. How do you use a priority queue for voice for the Ingress. Do you use policy-maps? can you use some sort of queuing such as LLQ on a switchport?


noxkrugger Thu, 05/01/2008 - 00:52

Yes, this is egress queue. For, the ingress, I didn't put any qos command as it was Ethernet network. I cannot use LLQ on a switchport. The command rejected.

mheusing Thu, 05/01/2008 - 01:29


As queueing is dependent on the specific implementation on a particular module, you need to check first, which number of queues are available and which number of thresholds. Note, not every module has a priority queue per port.

A quick check (in the lab first!) is to use "auto qos voip [trust|ciscophone]". This will essentially generate the appropriate configuration commands available from 12.2(33)SXH. You can modify them for your production environment. Have a look at "Using AutoQoS" for details

and at the command reference specifying the supported modules.

Another quite good source of information is the "Enterprise QoS Solution Reference Network Design Guide Version 3.3"

Check the section for the Catalyst 6500, which will give you queueing information for various switching modules.

Hope this helps! Please use the rating system.

Regards, Martin

jmcmasters Thu, 05/01/2008 - 05:49

We are currently running 12.2(18)SXF12a code. I have been debating on whether for the over 300Mbps worth of voice traffic is it worth migrating to SXH code for the auto qos voip feature for setting up the queues. Does anyone run WAN features on there 7600 such as BGP and OC circuits and have the SXH code?

mheusing Fri, 05/02/2008 - 14:51


You likely do not need to upgrade. auto qos is just an example of how to get a voip optimized QoS configuration. The config can then be applied to your production environment - with or without modifications.

Regards, Martin

Paolo Bevilacqua Thu, 05/01/2008 - 06:47

Hi, to the person that low rated my post above, evidently you have not come yet to the conclusion that in practice on gigabit interfaces, QoS in the form of LLQ for voice is not necessary, as things will work exactly the same whatever way you configure it.

Go ahead and try, report your findings here, but be fair and accurate a next time.


This Discussion