Comments on: Understanding Custom Queuing

By: Matt

Matt — Sat, 17 Apr 2010 04:36:16 +0000

Paul, yep it should. Wont get very far without applying “custom-queue-list 1″ to the interface

By: Paul

Paul — Fri, 13 Mar 2009 10:34:46 +0000

Should the Custom Queue configuration be assigned to the interface with “custom-queue-list 1” ?

By: Izack

Izack — Fri, 20 Feb 2009 22:53:55 +0000

Why use packet size to classify VOIP traffic rather than an ACL? Wouldn’t any small packet match this queue (telnet)? Also, the requirement says to give 10% bandwidth to ICMP which is assigned to queue 3. But then queue 3 is made the default queue which would receive all unclassified traffic wouldn’t it? Why not create a separate default queue? Thanks.

By: Dominik

Dominik — Thu, 22 Jan 2009 13:30:19 +0000

Where can I find this byte count calculation on Cisco website? Could you provide me the link to the source?

By: Petr Lapukhov, CCIE #16379

Petr Lapukhov, CCIE #16379 — Tue, 19 Aug 2008 03:15:25 +0000

To: michael

Yeah, thanks for noting that! I was re-typing the configuration instead of copy-pasting from the router config Fixed that now.

By: michael

michael — Mon, 18 Aug 2008 21:39:29 +0000

On R4, shouldn’t the configuration for RIP use udp instead of tcp? queue-list 1 protocol ip 0 tcp 520
shouldn’t this be queue-list 1 protocol ip 0 udp 520?

studying for this exam is causing me to pay attention to detail and question everything.

By: Petr Lapukhov, CCIE #16379

Petr Lapukhov, CCIE #16379 — Thu, 14 Aug 2008 08:14:28 +0000

To: Ivan Pepelnhak

The same goes to all legacy QoS technologies You want see many of those around nowdays, although I still use FR PIPQ at same places

However, I thkink it’s really useful to see how technologies evolved in their historical perspective. CQ is a nice illustration of RR scheduling, and seeing how it works gives people more insights on max-min resource sharing in general.

Besides, nobody says that aloud, but CBWFQ is really just the good old WFQ with some “enhancements”. Likewise, LLQ maps directly to IP RTP Priority. However, you can hardly find any information on internals of CBWFQ: e.g. how it computes weights values, how it handles Link Queues, and how it works when you have flow-based WFQ and manual classes configured at the same time.

Based on that, I believe that introducing new concepts following the evolutionary steps is much easier to understand than starting a breakdown of a new technlogy from a scratch.

By: Ivan Pepelnjak

Ivan Pepelnjak — Wed, 13 Aug 2008 18:25:31 +0000

Where would anyone use custom queuing these days (apart from the somewhat ridiculous tasks in the CCIE world)? Do you still see it used somewhere in new installations in real life?

By: NTllect

NTllect — Wed, 13 Aug 2008 09:59:34 +0000

thanks for the article, Petr!