I believe this is a misunderstanding.
the hold-queue limit is used to set the storing of packets by an
interface before dropping the packets.  So this is when the
transmission or recieving rate has already been reached.  I also
googled and found that there are several references that say this is
in relation to WFQ but I do not believe that to be the case.
Increasing the size of the interface queueing can greatly impact
performance on slow links.  the hold-queue is serviced by FIFO.

Here is the information from the command reference on Cisco's website.

Hold Queues and Priority Queueing

The hold queue stores packets received from the network that are
waiting to be sent to the client. It is recommended that the queue
size not exceed ten packets on asynchronous interfaces. For most other
interfaces, queue length should not exceed 100.

The input hold queue prevents a single interface from flooding the
network server with too many input packets. Further input packets are
discarded if the interface has too many input packets outstanding in
the system.

If priority output queueing is being used, the length of the four
output queues is set using the priority-list global configuration
command. The hold-queue command cannot be used to set an output hold
queue length in this situation.

For slow links, use a small output hold-queue limit. This approach
prevents storing packets at a rate that exceeds the transmission
capability of the link. For fast links, use a large output hold-queue
limit. A fast link may be busy for a short time (and thus require the
hold queue), but can empty the output hold queue quickly when capacity
returns.

To display the current hold queue setting and the number of packets
discarded because of hold queue overflows, use the show interfaces
command in EXEC mode.



--------------------------------------------------------------------------------

Caution Increasing the hold queue can have detrimental effects on
network routing and response times. For protocols that use seq/ack
packets to determine round trip times, do not increase the output
queue. Dropping packets instead informs hosts to slow down
transmissions to match available bandwidth. This is generally better
than having duplicate copies of the same packet within the network
(which can happen with large hold queues).


On Sat, May 3, 2008 at 9:56 PM, Scott Morris <[EMAIL PROTECTED]> wrote:
> It could very well be a change that does actually allow that to occur.  Did
> the command take on your 2811's?
>
> Previously though, it was to illustrate a line of thinking even though the
> command wouldn't take.
>
>
> Scott Morris, CCIE4 (R&S/ISP-Dial/Security/Service Provider) #4713, JNCIE-M
> #153, JNCIS-ER, CISSP, et al.
> CCSI/JNCI-M/JNCI-ER
> VP - Technical Training - IPexpert, Inc.
> IPexpert Sr. Technical Instructor
>
> [EMAIL PROTECTED]
>
>
>
> Telephone: +1.810.326.1444
> Fax: +1.810.454.0130
> http://www.ipexpert.com
>
>
>
>
>
> -----Original Message-----
> From: Suresh Mishra [mailto:[EMAIL PROTECTED]
> Sent: Saturday, May 03, 2008 3:43 PM
> To: Gary Duncanson
> Cc: [email protected]; Scott Morris
>
> Subject: Re: [OSL | CCIE_RS] hold queue on WFQ
>
> My typo error. Its task no 12.8 not 12.5.
>
>
> Suresh
>
> On Sat, May 3, 2008 at 3:25 PM, Gary Duncanson
> <[EMAIL PROTECTED]> wrote:
> > Suresh,
> >
> > I don't have or use the proctor guide. Which lab number is this from
> > workbook v 9.0?
> >
> > Thanks
> > Gary
> > ----- Original Message ----- From: "Suresh Mishra"
> > <[EMAIL PROTECTED]>
> > To: <[EMAIL PROTECTED]>; <[email protected]>
> > Sent: Saturday, May 03, 2008 8:08 PM
> > Subject: [OSL | CCIE_RS] hold queue on WFQ
> >
> >
> >
> >
> > > I am not sure if it may be the answer. The LAB task  12.5 requires
> > > us to put a limit on the number of packest for all the queue's in a
> > > WFQ system to 800.
> > >
> > > However, The proctor guide says that we need to use fair-queue
> > > aggregate-limt command for this which is only available on 7500.  So
> > > we can not do this for 2800 routers.
> > >
> > > However, I was going through the cisco doc and found this command
> > > called "hold-queue limit" which sets the limit on the total number
> > > of packets for the WFQ in all the queue's
> > >
> > > I just like to have a confirmation about this as this sounds to me
> > > like the real answer.
> > >
> > > Thanks
> > > Suresh
> > >
> >
> >
>
>



-- 
Tyson Scott - CCIE #13513 R&S and Security
Technical Instructor - IPexpert, Inc.

Telephone: +1.810.326.1444
Fax: +1.810.454.0130
Mailto: [EMAIL PROTECTED]

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