Default queue-limit ISR 4000's

[Douglas Bradfield]

Hello,

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

Thanks

[Philip D'Ath]

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

[Douglas Bradfield]

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.

[Joseph W. Doherty]

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages wha2tsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

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.

[Douglas Bradfield]

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

[Philip D'Ath]

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.

[Douglas Bradfield]

Its a layer 3 interface.