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RE: QOS and custom queueing(to CBWFQ) posted 06/29/2003
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The "remaining" keyword is apparantly something new with 12.1T later
trains or 12.2T ones.  CBWFQ is an evolving technology.  :)

1544000 is 100% of your bandwidth.  That is more than 75%, which is the
default max-reserved.  So you would have to change it.

If you use the priority command, that is in reference to the "real"
bandwidth.

If you use the bandwidth command, that is in reference to the "relative
bandwidth" after PQ stuff has been removed et al.

HTH,

Scott

PS.  This thought process has changed.  12.0T and 12.1 releases' logic
was a little different.



-----Original Message-----
From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On Behalf Of
John Matijevic
Sent: Sunday, June 29, 2003 11:38 AM
To: swm@xxxxxxxxxx; 'SHARMA,MOHIT (HP-Germany,ex1)'; 'Brian McGahan';
ccielab@xxxxxxxxxxxxxx
Subject: Re: QOS and custom queueing(to CBWFQ)


Scott,
Under the policy config, then go to your class statement thats where you
configure the bandwidth. I have a question where do you specify
bandwidth percent remaining? I do not see that as an option in 12.1
version. I only see bytes and bandwidth, no remaining option even after
I type the number of the bandwidth percent. Finally, when configuring
max-reserved-bandwith, its based on the bandwidth of the physical
interface, so you would do a sh int s0, for example, you have 1544 kb
which is 1544000 bytes. So then you would add up the total number of
bytes that you have allocated in the queue,s and as long as this does
not exceed 1544000, then you do not have to change
max-reserved-bandwidth.  The other way I have heard is to add up the
percentages allocated to each que, and if the percentages add up to
greater than 75% then you would add the command. Also the queue-limit I
have seen in configs where its set to 20, I remember hearing that 20 is
the default for CQ and 64 is default for CBWFQ... is there a reason you
need to specify the limit, if the question does not tell you
specifically to do so? Can you please confirm this. Sincerely, Matijevic

----- Original Message ----- 
From: "Scott Morris" <swm@xxxxxxxxxx>
To: "'SHARMA,MOHIT (HP-Germany,ex1)'" <mohit.sharma@xxxxxx>; "'Brian
McGahan'" <brian@xxxxxxxxxxxxxxx>; "'John Matijevic'"
<matijevi@xxxxxxxxxxxxx>; <ccielab@xxxxxxxxxxxxxx>
Sent: Sunday, June 29, 2003 11:02 AM
Subject: RE: QOS and custom queueing(to CBWFQ)


> Not exactly....
>
> Per: 
> http://www.cisco.com/en/US/tech/tk39/tk48/technologies_tech_note09186a
> 00
> 800fe2c1.shtml
>
> In Cisco IOS Software Releases 12.1T and 12.2,  the 
> max-reserved-bandwidth and the bandwidth percent commands are NOT 
> related. The bandwidth percent command is a relative percentage of 
> available bandwidth. The following example helps explain this:
>
> Interface bandwidth = 1000 kbps
> max reserved bandwidth = 75% default
>
> The priority (PQ) can be configured with a value of up to 75% or 750 
> kbps.
>
> The bandwidth percent command uses a ratio DERIVED FROM 1000 kbps - PQ

> bandwidth specified in priority statements.
>
> The max-reserved-bandwidth command does not affect the bandwidth 
> percentage, and the specified values in bandwidth percent commands can

> sum to higher than 75%.
>
> In addition, in these releases, the bandwidth percent command is used 
> as
> follows:
>
> "bandwidth percent" is an absolute percentage.
>
> "bandwidth percent remaining" allows you to dictate what percentage of

> unused bandwidth can be used by a class, rather than leaving it up to 
> calculated weightings, and so on.
>
> The max reserved bandwidth command specifies the amount of bandwidth 
> being allocated to fancy queueing. How this command affects bandwidth 
> allocations varies slightly with the Cisco IOS Release.
>
> If you exceed the max reserved bandwidth (for priority), then it
> changes:
>
> Cisco IOS Software Releases 12.1T and 12.2
>
> In Cisco IOS Software Releases 12.1T and 12.2, the percentages that 
> you define in your classes are a percentage of the max reserved 
> bandwidth value, rather than the full interface or VC bandwidth. The 
> following is an example using a T1 physical link and a class named 
> "Gold Class" with a priority percent 81 command.
>
> max_reserve_bw = .75 * 1544 =  1158
>
> Gold Class = .81 * 1158 = 937.98
>
> HTH,
>
> Scott
>
>
> -----Original Message-----
> From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On Behalf 
> Of SHARMA,MOHIT (HP-Germany,ex1)
> Sent: Saturday, June 28, 2003 2:19 PM
> To: 'Brian McGahan'; 'John Matijevic'; ccielab@xxxxxxxxxxxxxx
> Subject: RE: QOS and custom queueing(to CBWFQ)
>
>
> Hi Brian,John,
>
> Thanx a lot really for the explanatiion.
>
> I deduct from this, that my solution for turning John's custom queue 
> to CBWFQ is wrong, as it will just allocate the b/w caclulating on  
> the ''relative bandwitdh". Would it then be safe to say, that in cases

> like  this we should use the bandwdth command and not the bandwidth 
> percent?
>
> Just recieved John's mail also, and it seems that both the views are 
> quite conflicting, should we use the byte-count or the percentage? I 
> guess byte-count would be a safer bet. But then how can we get the 
> bandwidth amount to be allocated for each queue, in CBWFQ classes?  I 
> know I m asking too much, but would it be possible for you, to take 
> John's custom queue as an example and illustrate how we can do the 
> conversion, I guess a lot of people would be curious by now and all of

> us would be really grateful :-)
>
> Thanks as always,
>
> Smiles,
>
> Mohit
>
> -----Original Message-----
> From: Brian McGahan [mailto:brian@xxxxxxxxxxxxxxx]
> Sent: Saturday, June 28, 2003 7:34 PM
> To: 'SHARMA,MOHIT (HP-Germany,ex1)'; 'John Matijevic'; 
> ccielab@xxxxxxxxxxxxxx
> Subject: RE: QOS and custom queueing(to CBWFQ)
>
>
> Mohit,
>
> The 'bandwidth percent' command does a relative bandwidth reservation 
> based on the current available bandwidth of that interface. Available 
> bandwidth is calculated as follows:
>
> Available_Bandwidth = (Configured_Bandwidth *
> max-reserved-bandwidth/100) - (LLQ - RTP - RSVP)
>
> First take the 'bandwidth' statement configured on the interface and 
> multiply by the percentage that is reservable.  By default, 
> max-reserved-bandwidth is 75.  Then, subtract any bandwidth reserved 
> by priority queues, including the low latency queue (LLQ), real time 
> protocol (RTP), or resource reservation protocol (RSVP).  The 
> available bandwidth value can be seen when you 'show queue 
> [interface]':
>
> R1#sh queue fa0/0 | in Available
>      Available Bandwidth 75000 kilobits/sec
>
> Here we see a FastEthernet interface with no prior reservations. By 
> default, max-reserved-bandwidth is 75, therefore we have an available 
> bandwidth of 75Mbps.
>
> Now suppose we configure the following:
>
> class-map match-all FTP
>   match protocol ftp
> !
> policy-map QOS
>   class FTP
>    bandwidth percent 50
> !
> interface FastEthernet0/0
>  service-policy output QOS
> !
>
> R1#sh queue fa0/0 | in Available
>      Available Bandwidth 75000 kilobits/sec
>
> We are reserving 50% of the bandwidth on this interface for FTP. Since

> the available bandwidth on the interface is 75Mbps, and we are doing a

> percentage reservation, FTP is effectively guaranteed a minimum of 
> 37.5Mbps (50% of 75% of 100Mbps).
>
> If we actually want to reserve 50Mbps for FTP, we have three
> options:
>
> 1.  Set 'max-reserved-bandwidth' to 100
>
> interface FastEthernet0/0
>  max-reserved-bandwidth 100
>  service-policy output QOS
>
> R1#sh queue fa0/0 | in Available
>      Available Bandwidth 100000 kilobits/sec
>
> Since 100Mbps is now available on this interface, FTP is guaranteed 
> 50Mbps (50% of 100Mbps).
>
> 2.  Do an absolute 'bandwidth [kbps]' reservation
>
> class-map match-all FTP
>   match protocol ftp
> !
> policy-map QOS
>   class FTP
>    bandwidth 50000
> !
> interface FastEthernet0/0
>  service-policy output QOS
>
> R1#sh queue fa0/0 | in Available
>      Available Bandwidth 25000 kilobits/sec
>
> 'bandwidth [kbps]' is an absolute reservation, and is not based on the

> available bandwidth of the interface.  You can see that after 
> configuring 'bandwidth 50000' under the FTP class, only 25Mbps is now 
> available on the interface.
>
> 3.  Change the configured 'bandwidth' value on the interface
>
> While not very practical, we can adjust the bandwidth value on the 
> interface so that the following would be true:
>
> Interface_bandwidth = configured_bandwidth * 
> max-reserved-bandwidth/100
>
> Configured_bandwidth = interface_bandwidth * 
> 100/max-reserved-bandwidth
>
> interface FastEthernet0/0
>  bandwidth 133334
>  service-policy output QOS
>
> R1#sh queue fa0/0 | in Available
>      Available Bandwidth 100000 kilobits/sec
>
> While the third option is a roundabout solution, the point of the 
> exercise is to show that the available bandwidth is based on the 
> configured 'bandwidth' keyword, and not a function of the physical 
> interface.
>
>
> HTH
>
> Brian McGahan, CCIE #8593
> Director of Design and Implementation
> brian@xxxxxxxxxxxxxxx
>
> CyscoExpert Corporation
> Internetwork Consulting & Training
> Toll Free: 866.CyscoXP
> Fax: 847.674.2625
>
>
> > -----Original Message-----
> > From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On Behalf
> Of
> > SHARMA,MOHIT (HP-Germany,ex1)
> > Sent: Saturday, June 28, 2003 11:49 AM
> > To: 'John Matijevic'; ccielab@xxxxxxxxxxxxxx
> > Subject: RE: QOS and custom queueing(to CBWFQ)
> >
> > Hi John,
> >
> > Thanx for the same.
> >
> > Another one now. If you need to convert this queue into CBWFQ ( I 
> > saw
> a
> > post
> > from yesterday, but it was not "really"followed up", but got me
> thinking),
> > would you put the percentage in the policy map, as 50,25, 15 and 10,
> will
> > this allocate 75 percent of the interface bandwith?
> > I tried to implement it, but the available bandwith it shows is
> 7500kb, on
> > a
> > 10 mb interface. Quite confusing.-
> > here's the config-
> >
> > class-map match-any kl
> >   match protocol telnet
> >   match protocol ftp
> > class-map match-any hl
> >   match access-group 900
> >   match access-group 110
> > class-map match-any gl
> >   match input-interface Ethernet0/0
> >   match access-group 198
> >
> > policy-map look
> >   class kl
> >    bandwidth percent 40
> >   class hl
> >    bandwidth percent 25
> >   class gl
> >    bandwidth percent 15
> >   class class-default
> >    bandwidth percent 10
> >
> > interface Ethernet0/1
> >  ip address 10.15.1.3 255.255.255.0
> >  half-duplex
> >  service-policy output look
> > end
> >
> > oob-main-site#sh queueing interface e0/1
> > Interface Ethernet0/1 queueing strategy: fair
> >   Input queue: 0/75/0/0 (size/max/drops/flushes); Total output 
> > drops:
> 0
> >   Queueing strategy: weighted fair
> >   Output queue: 0/1000/64/0 (size/max total/threshold/drops)
> >      Conversations  0/1/256 (active/max active/max total)
> >      Reserved Conversations 4/4 (allocated/max allocated)
> >      Available Bandwidth 7500 kilobits/sec
> > <--------------------------------------
> >
> > Couls somebody please advice.
> >
> > Thanks,
> >
> > Mohit.
> >
> >
> > -----Original Message-----
> > From: John Matijevic [mailto:matijevi@xxxxxxxxxxxxx]
> > Sent: Saturday, June 28, 2003 6:16 PM
> > To: SHARMA,MOHIT (HP-Germany,ex1); ccielab@xxxxxxxxxxxxxx
> > Subject: Re: QOS and custom queueing
> >
> >
> > OK, Here we go:
> > In the example the workbook is using 10000 bytes, with 12.1 ios
> version
> > you
> > dont have to be specific in the byte count because it will borrow 
> > from
> the
> > next queue to be serviced.  So if you use 1000 bytes as a reference,
> 50%
> > would be 5000 bytes for queue1, 25% would be 2500 bytes for queue2,
> 15% is
> > 1500 for queue 3, you dont have to specify becuase the default bytes
> for a
> > queue is 1500 bytes, Since the calculation comes out to the same as
> the
> > defualt you do not need to specify.
> > Sincerely,
> > Matijevic
> > ----- Original Message -----
> > From: "SHARMA,MOHIT (HP-Germany,ex1)" <mohit.sharma@xxxxxx>
> > To: "'John Matijevic'" <matijevi@xxxxxxxxxxxxx>;
> <ccielab@xxxxxxxxxxxxxx>
> > Sent: Saturday, June 28, 2003 11:47 AM
> > Subject: RE: QOS and custom queueing
> >
> >
> > > Hi John,
> > >
> > > Could you please xplain, why is the byte count for specifically
> queue 3
> > is
> > > missing and why 10K?
> > >
> > > Yu kind of got me confused with your example :-)
> > >
> > > Thanx,
> > >
> > > Mohit.
> > >
> > > -----Original Message-----
> > > From: John Matijevic [mailto:matijevi@xxxxxxxxxxxxx]
> > > Sent: Friday, June 27, 2003 10:22 PM
> > > To: John Matijevic; ccielab@xxxxxxxxxxxxxx
> > > Subject: Re: QOS and custom queueing
> > >
> > >
> > > Thanks all,
> > > I got the answer it looks like it is based off of 10000 bytes and
> with
> > IOS
> > > 12.1 you do not need to be specific and can user whatever number 
> > > you
> > want
> > if
> > > its not given.
> > > Sincerely,
> > > Matijevic
> > > ----- Original Message -----
> > > From: "John Matijevic" <matijevi@xxxxxxxxxxxxx>
> > > To: <ccielab@xxxxxxxxxxxxxx>
> > > Sent: Friday, June 27, 2003 3:11 PM
> > > Subject: QOS and custom queueing
> > >
> > >
> > > > Hello Team,
> > > > I have the following scenerio:
> > > > queue-list 1 protocol ip 1 tcp telnet
> > > > queue-list 1 protocol ip 1 tcp ftp
> > > > queue-list 1 protocol ipx 2
> > > > queue-list 1 protocol ip 2 list 101
> > > > queue-list 1 protocol ip 3 gt 1200
> > > > queue-list 1 interface Ethernet0 3
> > > > queue-list 1 default 4
> > > >
> > > > Basically I have 4 queues and the question asks to configure
> Custom
> > > Queueing
> > > > so that 50% of bandwidth go to que 1, 25% goes to que 2, 15% 
> > > > goest
> to
> > que
> > > 3,
> > > > and 10% goes to que 4.
> > > > The answer is the following:
> > > > queue-list 1 queue 1 byte-count 5000
> > > > queue-list 1 queue 2 byte-count 2500
> > > > queue-list 1 queue 4 byte-count 1000
> > > > My question is how the numbers get derived in the answer? I am
> > thinking
> > > that
> > > > they are using 10000 kilobytes as a reference, i think it may be
> > because
> > > since
> > > > ethernet 0 is in one of the queues that its bandwidth is 
> > > > 10000kb,
> but
> > I
> > am
> > > not
> > > > a 100% sure, I think that the default you use is 1500 bytes, and
> since
> > > there
> > > > are 4 queues I thought it would be 6000, since they dont say the
> byte
> > > count of
> > > > each queue.  how do you come up with this?  Also I think there
> should
> > be
> > > > another que in the answer, queue-list 1 queue 3 byte-count 1500,
> Could
> > > someone
> > > > help me clarify?
> > > > Sincerely,
> > > > Matijevic
> > > >
> > > >
> > > >
> >
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