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Default queue-limit ISR 4000's


I am trying to locate the default queue limit for class based QOS on the ISR 4000's series routers. 


6 Replies 6

Philip D'Ath
VIP Alumni
VIP Alumni

Could you post a bit of your policy?  There are many different types of queueing and congestion control systems.

Its not about the policy. I just need to know what the default queue limit is. For example, the default for ISR G2's is 64 packets. On an ASR 1000 it is 833 packets.


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Default queue limits may vary between platforms, and also may vary between IOS versions.

Configuration may matter, because the default CBWFQ queue-limit might vary depending whether the class is configured to use FIFO or FQ.  (Again, IOS versions can vary defaults, such as between pre-HQF and post-HQF, but likely any ISR 4K is post-HQF.)

On some CBWFQs, I believe when FQ is enabled, default queue-limit varies based on what CBWFQ believes the available bandwidth is.

I don't know whether defaults are documented anywhere.  Likely, you many need access to the actual platform/IOS and see what it does configured as you needed.

BTW, newer IOSs usually allow you to change the default, but I recall older IOSs did not.

We often change the default per COS bucket based on what applications, IP address ranges, etc. We only have one in production and we didn't look at it before hand. I too, couldn't find it anywhere what it was set to out of the box. I guess I'll have to wait until I stand up another one to see what is configured. Thanks

Are you talking about a later 3 interface?  A switch blade interface? An SVI interface?  An ATM interface?  A 4G interface?  Some other kind of interface?

And yes, the queue limit can be affected by the type of policy.

If you wont share the policy, how about telling us just the interface type so we can try and give you the hardware defaults for that type.

Its a layer 3 interface.

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