Hi; First, sorry if this question is mostly netfilter related, than lartc, but I think you guys may have a your opinion about this. I''m using Linux 2.4.x with netfilter packet filtering / NAT on our front-end firewalls (P500 with 1Gb RAM), which are filtering traffic going to our Public Web Sites. The traffic is growing very fast since several months.. The average traffic filtered by our firewalls, is around 30/40 Mbits/s, with peaks around 70 Mbits/s sometimes, so that we had to switch to gigabit technologies, to keep a good safe margin. Our firewalls are not so high speed machines (P500 with 1Gb RAM), but are doing good so far. It seems, however, that we are reaching the limits, when approaching 70 Mb/s... cpu utilization is then near 100%, and the machines start dropping packets. So, my question is, is netfilter able to handle, let''s say gigabit traffic filtering ? What kind of hardware would be necessary to handle such traffic ? Have you guys any experience with filtering such high speed traffic ? I also thought of two possible solutions, to optimize our current firewalls, on which you may have an opinion. 1) Disabling statefull inspection, by unloading connection tracking modules. I believe netfilter without connection tracking, might be much more efficient (We don''t need connection tracking actually, since we are only filtering HTTP traffic from the others traffics at this point) 2) Replace iptables by nf-hipac for packet filtering. Have you guys any experience with nf-hipac ? (http://www.hipac.org/) I would be really thanksfull to hear of any solutions / workarounds / optimization to keep our linux firewalls handling growing traffic :-) Thanks ! Vincent. --- Vincent Jaussaud Kelkoo.com Security Manager email: tatooin@kelkoo.com "Those who desire to give up freedom in order to gain security will not have, nor do they deserve, either one." -- President Thomas Jefferson. 1743-1826 _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/
Vincent Jaussaud wrote:> Hi; > > First, sorry if this question is mostly netfilter related, than lartc, > but I think you guys may have a your opinion about this.You should post this question to the netfilter-devel list, people there can give you very good advice.> > I''m using Linux 2.4.x with netfilter packet filtering / NAT on our > front-end firewalls (P500 with 1Gb RAM), which are filtering traffic > going to our Public Web Sites. > > The traffic is growing very fast since several months.. The average > traffic filtered by our firewalls, is around 30/40 Mbits/s, with peaks > around 70 Mbits/s sometimes, so that we had to switch to gigabit > technologies, to keep a good safe margin. > > Our firewalls are not so high speed machines (P500 with 1Gb RAM), but > are doing good so far. > > It seems, however, that we are reaching the limits, when approaching 70 > Mb/s... cpu utilization is then near 100%, and the machines start > dropping packets. > > So, my question is, is netfilter able to handle, let''s say gigabit > traffic filtering ? What kind of hardware would be necessary to handle > such traffic ? > > Have you guys any experience with filtering such high speed traffic ?Netfilter sure is able to handle 1gbit, but it doesn''t depend that much on the raw speed. The number of conntracks and simultaneos active connections matters much more.> I also thought of two possible solutions, to optimize our current > firewalls, on which you may have an opinion. > > 1) Disabling statefull inspection, by unloading connection tracking > modules. > I believe netfilter without connection tracking, might be much more > efficient (We don''t need connection tracking actually, since we are only > filtering HTTP traffic from the others traffics at this point)That might help, although without stateful filtering the rules have to be evaluated for each single packet.> 2) Replace iptables by nf-hipac for packet filtering. Have you guys any > experience with nf-hipac ? (http://www.hipac.org/)nf-hipac is very good with a large number of rules, for just http filtering I suspect iptables will do equally good or better.> > I would be really thanksfull to hear of any solutions / workarounds / > optimization to keep our linux firewalls handling growing traffic :-)Try without conntrack if you don''t need it, otherwise start with increasing the hash table size and limit ip_conntrack_max to 2 times the hash size. There was a thread about optimizing iptables on netfilter-devel 1-2 month ago, it was started by Hervé Eychenne, search the archives. Best regards, Patrick> > Thanks ! > Vincent. > > --- > > Vincent Jaussaud > Kelkoo.com Security Manager > email: tatooin@kelkoo.com > > "Those who desire to give up freedom in order to gain security will not > have, nor do they deserve, either one." > -- President Thomas Jefferson. 1743-1826 > > > _______________________________________________ > LARTC mailing list / LARTC@mailman.ds9a.nl > http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/_______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/
On Sat, 2004-01-10 at 00:10, Patrick McHardy wrote:> Vincent Jaussaud wrote: > > Hi;Hi, and thanks for you reply.> >> That might help, although without stateful filtering the rules > have to be evaluated for each single packet.Okay, we''ll give it a try.> > > > 2) Replace iptables by nf-hipac for packet filtering. Have you guys any > > experience with nf-hipac ? (http://www.hipac.org/) > > nf-hipac is very good with a large number of rules, for just http > filtering I suspect iptables will do equally good or better.To be tested then, ok I''ll try to see if we could build a test network and try to simulate such traffic.> > > > > I would be really thanksfull to hear of any solutions / workarounds / > > optimization to keep our linux firewalls handling growing traffic :-) > > Try without conntrack if you don''t need it, otherwise start with > increasing the hash table size and limit ip_conntrack_max to 2 times > the hash size. There was a thread about optimizing iptables on > netfilter-devel 1-2 month ago, it was started by Hervé Eychenne, > search the archives.Thanks, I found the post. Indeed, there is a lot of helpful informations within. I''ll investigate these post deeper. Thanks ! Regards, Vincent.> > Best regards, > Patrick > > > > > Thanks ! > > Vincent. > > > > --- > > > > Vincent Jaussaud > > Kelkoo.com Security Manager > > email: tatooin@kelkoo.com > > > > "Those who desire to give up freedom in order to gain security will not > > have, nor do they deserve, either one." > > -- President Thomas Jefferson. 1743-1826 > > > > > > _______________________________________________ > > LARTC mailing list / LARTC@mailman.ds9a.nl > > http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/-- Vincent Jaussaud Kelkoo.com Security Manager email: tatooin@kelkoo.com "Those who desire to give up freedom in order to gain security will not have, nor do they deserve, either one." -- President Thomas Jefferson. 1743-1826 _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/