LARTC - Nov 2004 - kernel configuration and tc commands for traffic shaping

Hi,

I wished to shape the traffic that cross my ppp0 interface 
so I asked around and google''d a bit and I headed in the 
LARTC HOWTO.

As stated in the early in the text, as the title implies, 
that is an "Advanced" HOWTO and while by no means rocket 
science, some prior knowledge is assumed.

Unfortunately I found myself lost very soon and I''m 
writing here in hope of some help.


What I''d like to do, if it were possible with some 
iptables switch, would be something like the following.

  iptables --insert INPUT --in-interface ppp0 \
           --protocol tcp --destination-port 80 \
           --source $SOMEIPADDRESS \
           --jump SHAPING --limit-to 10KBs

Of course the last line is pure fiction =) but I thought 
it would have explained what I wished to do pretty well.

Shaping the traffic according to some --source switch 
isn''t a priority at the moment but it would be nice to, 
anyhow.


After some reading I found out that what I wished to do 
is very likely called "traffic shaping". So I searched 
the text for "shaping" and I found a note saying that, if 
all I wanted to do is simple traffic shaping, I could have 
skipped everything and headed to the Other possibilities 
chapter, and readed about CBQ.init.

Unforntunately, as stated below, by all means CBQ.init is 
useful if the ''how and why'' don''t interest me, but
they
do, actually.

I tried both the CBQ.init and the HTB.init scripts but 
they were huge, I wasn''t able to understand them and I 
didn''t managed to find any information about how to 
configure the kernel.

Of course, I could check out everything in the QoS section
in menuconfig during the kernel configuration but I''d like
to understand which support I would actually use.


At least, after having tried to read them, I realized 
that, if I understood well, what I wish to do should be 
possible only using tc, not iptables.


Could you please help me to find out which commands to 
type and how to configure the kernel in order to 
accomplish my task?

I''d need something in the middle between the "rocket 
science" of LARTC and the "how and why don''t interest
you"
of CBQ.init.



Scuse me if some of my questions are FAQs.

Thanks in advance.

Best regards.
-- 
Value your freedom, or you will lose it, teaches history. 
``Don''t bother us with politics,'''' respond those who
don''t
want to learn.

 -- Richard M. Stallman
    http://www.gnu.org/philosophy/linux-gnu-freedom.html

You can try this (adapted from
http://www.knowplace.org/shaper/examples.html):

tc qdisc add dev ppp0 root handle 1: htb default 60   
tc class add dev ppp0 parent 1:1 classid 1:10 htb rate 10kbit ceil
$MAXSPEEDkbit prio 0
tc filter add dev ppp0 protocol ip parent 1:0 protocol ip prio 1 u32 \
	match ip dport 80 0xffff \
	match ip src $SOMEIPADDRESS \
	police rate 10kbit flowid 1:10
	

             Antonio Luiz 

> -----Mensagem original-----
> De: lartc-admin@mailman.ds9a.nl 
> [mailto:lartc-admin@mailman.ds9a.nl] Em nome de ncrfgs
> Enviada em: quinta-feira, 25 de novembro de 2004 14:17
> Para: lartc@mailman.ds9a.nl
> Assunto: [LARTC] kernel configuration and tc commands for 
> traffic shaping
> 
> 
> Hi,
> 
> I wished to shape the traffic that cross my ppp0 interface 
> so I asked around and google''d a bit and I headed in the 
> LARTC HOWTO.
> 
> As stated in the early in the text, as the title implies, 
> that is an "Advanced" HOWTO and while by no means rocket 
> science, some prior knowledge is assumed.
> 
> Unfortunately I found myself lost very soon and I''m 
> writing here in hope of some help.
> 
> 
> What I''d like to do, if it were possible with some 
> iptables switch, would be something like the following.
> 
>   iptables --insert INPUT --in-interface ppp0 \
>            --protocol tcp --destination-port 80 \
>            --source $SOMEIPADDRESS \
>            --jump SHAPING --limit-to 10KBs
> 
> Of course the last line is pure fiction =) but I thought 
> it would have explained what I wished to do pretty well.
> 
> Shaping the traffic according to some --source switch 
> isn''t a priority at the moment but it would be nice to, 
> anyhow.
> 
> 
> After some reading I found out that what I wished to do 
> is very likely called "traffic shaping". So I searched 
> the text for "shaping" and I found a note saying that, if 
> all I wanted to do is simple traffic shaping, I could have 
> skipped everything and headed to the Other possibilities 
> chapter, and readed about CBQ.init.
> 
> Unforntunately, as stated below, by all means CBQ.init is 
> useful if the ''how and why'' don''t interest me,
but they
> do, actually.
> 
> I tried both the CBQ.init and the HTB.init scripts but 
> they were huge, I wasn''t able to understand them and I 
> didn''t managed to find any information about how to 
> configure the kernel.
> 
> Of course, I could check out everything in the QoS section
> in menuconfig during the kernel configuration but I''d like
> to understand which support I would actually use.
> 
> 
> At least, after having tried to read them, I realized 
> that, if I understood well, what I wish to do should be 
> possible only using tc, not iptables.
> 
> 
> Could you please help me to find out which commands to 
> type and how to configure the kernel in order to 
> accomplish my task?
> 
> I''d need something in the middle between the "rocket 
> science" of LARTC and the "how and why don''t interest
you"
> of CBQ.init.
> 
> 
> 
> Scuse me if some of my questions are FAQs.
> 
> Thanks in advance.
> 
> Best regards.
> -- 
> Value your freedom, or you will lose it, teaches history. 
> ``Don''t bother us with politics,'''' respond those
who don''t
> want to learn.
> 
>  -- Richard M. Stallman
>     http://www.gnu.org/philosophy/linux-gnu-freedom.html
> 
_______________________________________________
LARTC mailing list / LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/

Hi,

   First of all, you have to know what you really want. What
discipline will you use, what kind of filtering you''ll implement. Such
simple and not abstract questions will have the answers in the LARTC
document if you read it profusely. CBQ or HTB? (I''d prefer HTB
myself). u32 or FWMARK? Then you''ll know which kernel options are to
be set and which tools you''ll need: iproute2 tc tool and iptables or
just iptables.
   After that, everything will be just syntax and logics.


On Thu, 25 Nov 2004 18:17:09 +0100, ncrfgs <ncrfgs@tin.it>
wrote:
> Hi,
> 
> I wished to shape the traffic that cross my ppp0 interface
> so I asked around and google''d a bit and I headed in the
> LARTC HOWTO.
> 
> As stated in the early in the text, as the title implies,
> that is an "Advanced" HOWTO and while by no means rocket
> science, some prior knowledge is assumed.
> 
> Unfortunately I found myself lost very soon and I''m
> writing here in hope of some help.
> 
> What I''d like to do, if it were possible with some
> iptables switch, would be something like the following.
> 
>   iptables --insert INPUT --in-interface ppp0 \
>            --protocol tcp --destination-port 80 \
>            --source $SOMEIPADDRESS \
>            --jump SHAPING --limit-to 10KBs
> 
> Of course the last line is pure fiction =) but I thought
> it would have explained what I wished to do pretty well.
> 
> Shaping the traffic according to some --source switch
> isn''t a priority at the moment but it would be nice to,
> anyhow.
> 
> After some reading I found out that what I wished to do
> is very likely called "traffic shaping". So I searched
> the text for "shaping" and I found a note saying that, if
> all I wanted to do is simple traffic shaping, I could have
> skipped everything and headed to the Other possibilities
> chapter, and readed about CBQ.init.
> 
> Unforntunately, as stated below, by all means CBQ.init is
> useful if the ''how and why'' don''t interest me,
but they
> do, actually.
> 
> I tried both the CBQ.init and the HTB.init scripts but
> they were huge, I wasn''t able to understand them and I
> didn''t managed to find any information about how to
> configure the kernel.
> 
> Of course, I could check out everything in the QoS section
> in menuconfig during the kernel configuration but I''d like
> to understand which support I would actually use.
> 
> At least, after having tried to read them, I realized
> that, if I understood well, what I wish to do should be
> possible only using tc, not iptables.
> 
> Could you please help me to find out which commands to
> type and how to configure the kernel in order to
> accomplish my task?
> 
> I''d need something in the middle between the "rocket
> science" of LARTC and the "how and why don''t interest
you"
> of CBQ.init.
> 
> Scuse me if some of my questions are FAQs.
> 
> Thanks in advance.
> 
> Best regards.
> --
> Value your freedom, or you will lose it, teaches history.
> ``Don''t bother us with politics,'''' respond those
who don''t
> want to learn.
> 
>  -- Richard M. Stallman
>     http://www.gnu.org/philosophy/linux-gnu-freedom.html
> 
> 
> 

-- 
Aghi
<ahollanda % gmail dot com>
_______________________________________________
LARTC mailing list / LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/

On Thu, Nov 25, 2004 at 03:46:32PM -0300, Antonio Luiz
wrote:
> You can try this (adapted from
> http://www.knowplace.org/shaper/examples.html):
> 
>   tc qdisc add dev ppp0 root handle 1: htb default 60   
>   tc class add dev ppp0 parent 1:1 classid 1:10 htb rate 10kbit ceil \
>             $MAXSPEEDkbit prio 0
>   tc filter add dev ppp0 protocol ip parent 1:0 protocol ip prio 1 u32 \
>             match ip dport 80 0xffff \
>             match ip src $SOMEIPADDRESS \
>             police rate 10kbit flowid 1:10
Very useful link and code.


I changed it a bit, though. This is what I used.

    tc qdisc add dev ppp0 root handle 1: htb
    tc class add dev ppp0 parent 1: classid 1:1 htb rate $MAXSPEEDkbit
    iptables --table mangle --insert POSTROUTING \
             --protocol tcp \
             --source $IPADDRESS --destination-port 80 \
             --jump CLASSIFY --set-class 1:1


Here are some consideration, though.

- Isn''t ''default'' supposed to suggest a default
subclass
  id? What does the 60 in your ''tc qdisc'' line refer to?


- The parent you specified in ''tc class'' line''
doesn''t
  exist as far as I understood. If I type that command it 
  seems to work anyhow. What am I missing?


- What does the parent in your ''tc filter'' line refer to?
 

- I assume $MAXSPEED is the speed you that traffic to be 
  shaped like. I used ''rate $MAXSPEEDkbit'' instead of 
  ''rate 10kbit ceil $MAXSPEEDkbit'' and it seems to work.
  What is the difference betweem these two versions?


- Instead of the ''tc filter'' line I used a iptables rule. 
  This way I was able to add to the kernel just the HTB 
  support. Otherwise as far as I understood I would have 
  had to add other filter related things.

  Furthermore http://www.knowplace.org/shaper/ suggests to 
  use iptables CLASSIFY when possible. What do you think 
  about it? What are the advantages and disadvantage of 
  the approaches reported?

    1) tc filter
    2) iptables marking with tc filter
    3) iptables classify


  Personally I love the third. It''s very human readable 
  and, if I understood well, once you set a class with 
  the same name on every interface, with iptables you can 
  use just a single line to filter all the packets while 
  with tc filter you would have to specify a filter for 
  every single interface.


- Why did you use a source-ip/destination-port combination 
  instead of a destination-ip/source-port one?



Thanks in advance.

Best regards.
-- 
Value your freedom, or you will lose it, teaches history. 
``Don''t bother us with politics,'''' respond those who
don''t
want to learn.

 -- Richard M. Stallman
    http://www.gnu.org/philosophy/linux-gnu-freedom.html

On Thursday 25 November 2004 12:17, ncrfgs wrote:
> Hi,
>
<snip>
> I''d need something in the middle between the "rocket
> science" of LARTC and the "how and why don''t interest
you"
> of CBQ.init.
>
You could always check out my Linux traffic control guide[1].

[1] http://trekweb.com/~jasonb/articles/traffic_shaping/
>
> Scuse me if some of my questions are FAQs.
>
> Thanks in advance.
>
> Best regards.
-- 

Jason Boxman
Perl Programmer / *NIX Systems Administrator
Shimberg Center for Affordable Housing | University of Florida
http://edseek.com/ - Linux and FOSS stuff

_______________________________________________
LARTC mailing list / LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/