[LARTC] TBF algorithm/usage

[LARTC] TBF algorithm/usage

[Radu-Mihail Obada]

Hello everyone,
I have a (mini) Linux router, which goes "out" through eth0; eth0 is
capable of almost 2Mbit of bandwith (well, actually it's like 10Mbit,
but you wouldn't care less). Now, say I want to limit _everything_, like
in every connection. So naturally, after carefully reading the man pages
and that excellent HOWTO, I resort to TBF. I fiddle a lit with this, but
after a couple of hours of intense experimentation, I find that it
doesn't do what I really want it to.
Specifically, I want _every_ connection to use _at most_ (say) 16kbps, never 
more, even if there is some bandwidth to borrow from. But TBF doesn't
seem to do just that (or I don't understand its inner working, which I
kinda don't). And what does burst mean/do? tc-tbf(8) says that I would
never need to modify this, but tc qdisc add ... root tbf always requires
it.
Thanks in advance.

-- 
Radu-Mihail Obada

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

Re: [LARTC] TBF algorithm/usage

[Stef Coene]

On Tuesday 10 December 2002 15:51, Radu-Mihail Obada wrote:
> Hello everyone,
> I have a (mini) Linux router, which goes "out" through eth0; eth0 is
> capable of almost 2Mbit of bandwith (well, actually it's like 10Mbit,
> but you wouldn't care less). Now, say I want to limit _everything_, like
> in every connection. So naturally, after carefully reading the man pages
> and that excellent HOWTO, I resort to TBF. I fiddle a lit with this, but
> after a couple of hours of intense experimentation, I find that it
> doesn't do what I really want it to.
> Specifically, I want _every_ connection to use _at most_ (say) 16kbps,
> never more, even if there is some bandwidth to borrow from. But TBF doesn't
> seem to do just that (or I don't understand its inner working, which I
> kinda don't). And what does burst mean/do? tc-tbf(8) says that I would
> never need to modify this, but tc qdisc add ... root tbf always requires
> it.
> Thanks in advance.
Tbf limits all bandwidth that leaves the NIC.  What you want to do, limit each 
connection to a certain bandwidth, is not so easy to implement.  If you want 
to do it per ip-address, or port, you can create a cbq or htb setup.  So you 
can put each connection in a different class and limit the speed it can get.  
The filtering can be done on ports and/or ip-addresses.  But if you want a 
class for each connection, you will need a lot of classes.

Stef

-- 

stef.coene@docum.org
 "Using Linux as bandwidth manager"
     http://www.docum.org/
     #lartc @ irc.oftc.net

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

Re: [LARTC] TBF algorithm/usage

[Radu-Mihail Obada]

Ok, I guess I got the point. And I think this is not exactly what I want to
do. Thanks for your help.
> Tbf limits all bandwidth that leaves the NIC.  What you want to do, limit each 
> connection to a certain bandwidth, is not so easy to implement.  If you want 
> to do it per ip-address, or port, you can create a cbq or htb setup.  So you 
> can put each connection in a different class and limit the speed it can get.  
> The filtering can be done on ports and/or ip-addresses.  But if you want a 
> class for each connection, you will need a lot of classes.
> 
> Stef
> 
> -- 
> 
> stef.coene@docum.org
>  "Using Linux as bandwidth manager"
>      http://www.docum.org/
>      #lartc @ irc.oftc.net
> 

-- 
Radu-Mihail Obada
System administrator & web programmer,
Faculty of Mathematics and Computer Science,
University of Bucharest
_______________________________________________
LARTC mailing list / LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/