Hi!
I really need help with a u32 filter that won''t match what I think
I''m
telling it to. The situation is that I have set up an internal
computer to change the TOS value of packets sent by certain processes
to 0x1E (If anyone known of a better way to mark packets, please tell
me. I would love to find some module that adds an IP option with UIDs
and GIDs to the packets - does anyone know if such a module already
exists?), and I want my router to deprioritize them. I also want to
limit my outbound bandwidth to 750kbit overall. So anyway, this is my
qdisc setup:
tc qdisc add dev eth1 root handle 1: cbq bandwidth 10mbit \
avpkt 1000 rate 750kbit cell 8
tc qdisc add dev eth1 parent 1: handle 2: prio bands 4
tc qdisc add dev eth1 parent 2:1 handle 3: sfq perturb 10
tc qdisc add dev eth1 parent 2:2 handle 4: sfq perturb 10
tc qdisc add dev eth1 parent 2:3 handle 5: sfq perturb 10
tc qdisc add dev eth1 parent 2:4 handle 6: sfq perturb 5
So far so good. All packets go to the right qdisc among 3: - 5: (As
seen with "tc -s qdisc ls"). However, when I add the filter to make
packets with TOS 0x1E go to 6:, I set it up like this:
tc filter add dev eth1 parent 1: protocol ip prio 1 \
u32 match ip tos 0x1e 0xff flowid 6:
I am under the impression that it should be done like that. However,
that filter simply doesn''t match the packets. I have tried some
combinations, like setting the flowid to 2:4 instead or using parent
2:. (The strange thing is that when I used "parent 2:", no filter was
added at all... What''s up with that?) Also, in case you''re
wondering,
I have checked so that the packets actually are marked with TOS=0x1E,
and they are.
I''m sure I have just missed something and am wasting your time, but
please, I just can''t see what I''m missing...
Oh, and by the way, it would be nice to unmark the packets again
before they go out, and setting up an iptables rule for that is, of
course, very simple. However, since that happens before the packets
are enqueued, that removes the mark before the filters are classified,
which isn''t really my intention... Is there any other way of demarking
the packets that doesn''t interfere with the QoS setup?
Thank you very much for your time!
Fredrik Tolf
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On Sunday 23 November 2003 05:03, Fredrik Tolf wrote:> Hi! > > I really need help with a u32 filter that won''t match what I think I''m > telling it to. The situation is that I have set up an internal > computer to change the TOS value of packets sent by certain processes > to 0x1E (If anyone known of a better way to mark packets, please tell > me. I would love to find some module that adds an IP option with UIDs > and GIDs to the packets - does anyone know if such a module already > exists?), and I want my router to deprioritize them. I also want to > limit my outbound bandwidth to 750kbit overall. So anyway, this is my > qdisc setup: > > tc qdisc add dev eth1 root handle 1: cbq bandwidth 10mbit \ > avpkt 1000 rate 750kbit cell 8 > tc qdisc add dev eth1 parent 1: handle 2: prio bands 4 > tc qdisc add dev eth1 parent 2:1 handle 3: sfq perturb 10 > tc qdisc add dev eth1 parent 2:2 handle 4: sfq perturb 10 > tc qdisc add dev eth1 parent 2:3 handle 5: sfq perturb 10 > tc qdisc add dev eth1 parent 2:4 handle 6: sfq perturb 5 > > So far so good. All packets go to the right qdisc among 3: - 5: (As > seen with "tc -s qdisc ls"). However, when I add the filter to make > packets with TOS 0x1E go to 6:, I set it up like this: > > tc filter add dev eth1 parent 1: protocol ip prio 1 \ > u32 match ip tos 0x1e 0xff flowid 6:You are making a lot of errors. You add a root cbq qdisc, that''s fine, but you need to add a class if you want to bound it to a rate. If you add a filter to a qdisc, it has to point to a class of that qdisc. Not to an other class.> I am under the impression that it should be done like that. However, > that filter simply doesn''t match the packets. I have tried some > combinations, like setting the flowid to 2:4 instead or using parent > 2:. (The strange thing is that when I used "parent 2:", no filter was > added at all... What''s up with that?)Try tc -s -d filter show dev eth1 parent 2: Stef -- stef.coene@docum.org "Using Linux as bandwidth manager" http://www.docum.org/ #lartc @ irc.openprojects.net _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/
Stef Coene writes: > On Sunday 23 November 2003 05:03, Fredrik Tolf wrote: > > So anyway, this is my qdisc setup: > > > > tc qdisc add dev eth1 root handle 1: cbq bandwidth 10mbit \ > > avpkt 1000 rate 750kbit cell 8 > > tc qdisc add dev eth1 parent 1: handle 2: prio bands 4 > > tc qdisc add dev eth1 parent 2:1 handle 3: sfq perturb 10 > > tc qdisc add dev eth1 parent 2:2 handle 4: sfq perturb 10 > > tc qdisc add dev eth1 parent 2:3 handle 5: sfq perturb 10 > > tc qdisc add dev eth1 parent 2:4 handle 6: sfq perturb 5 > > > > So far so good. All packets go to the right qdisc among 3: - 5: (As > > seen with "tc -s qdisc ls"). However, when I add the filter to make > > packets with TOS 0x1E go to 6:, I set it up like this: > > > > tc filter add dev eth1 parent 1: protocol ip prio 1 \ > > u32 match ip tos 0x1e 0xff flowid 6: > You are making a lot of errors. You add a root cbq qdisc, that''s fine, but > you need to add a class if you want to bound it to a rate. I see. That does explain a lot of things I haven''t been able to pull together, actually. Thank you very much for pointing that out. > If you add a filter to a qdisc, it has to point to a class of that > qdisc. Not to an other class. That confuses me a bit. It does certainly make it work, and it does certainly make sense. However, in the advanced routing howto, section 9.5.2.1, it seems to very much implicate that you can create filters like that. Is that howto wrong or did I misinterpret something? If you want to see it, follow this URL: http://www.tldp.org/HOWTO/Adv-Routing-HOWTO/lartc.qdisc.classful.html > > (The strange thing is that when I used "parent 2:", no filter was > > added at all... What''s up with that?) > Try > tc -s -d filter show dev eth1 parent 2: Hehe... Don''t I feel stupid now... Oh well, at least now I know (I thought all filters were in a per-interface namespace). Thank you for pointing that out. _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/
On Sunday 23 November 2003 14:44, Fredrik Tolf wrote:> > If you add a filter to a qdisc, it has to point to a class of that > > qdisc. Not to an other class. > > That confuses me a bit. It does certainly make it work, and it does > certainly make sense. However, in the advanced routing howto, section > 9.5.2.1, it seems to very much implicate that you can create filters > like that. Is that howto wrong or did I misinterpret something? If you > want to see it, follow this URL: > > http://www.tldp.org/HOWTO/Adv-Routing-HOWTO/lartc.qdisc.classful.htmlI know. You can do it. You can point your filter to a class of an other qdisc and it will work, but not always like expected. To be safe, use filters within the same qdisc.> > > (The strange thing is that when I used "parent 2:", no filter was > > > added at all... What''s up with that?) > > > > Try > > tc -s -d filter show dev eth1 parent 2: > > Hehe... Don''t I feel stupid now... Oh well, at least now I know (I > thought all filters were in a per-interface namespace). Thank you for > pointing that out.I made the same mistake before :) Stef -- stef.coene@docum.org "Using Linux as bandwidth manager" http://www.docum.org/ #lartc @ irc.openprojects.net _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/
Stef Coene writes: > On Sunday 23 November 2003 14:44, Fredrik Tolf wrote: > > > If you add a filter to a qdisc, it has to point to a class of that > > > qdisc. Not to an other class. > > > > That confuses me a bit. It does certainly make it work, and it does > > certainly make sense. However, in the advanced routing howto, section > > 9.5.2.1, it seems to very much implicate that you can create filters > > like that. Is that howto wrong or did I misinterpret something? If you > > want to see it, follow this URL: > > > > http://www.tldp.org/HOWTO/Adv-Routing-HOWTO/lartc.qdisc.classful.html > I know. You can do it. You can point your filter to a class of an other > qdisc and it will work, but not always like expected. To be safe, use > filters within the same qdisc. I see. Maybe I should mail the author and encourage him to point it out. Thanks for all your help. Fredrik Tolf _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/