>>> On 22/05/2008 at 16:57, in message <483589C0.4080006@xxxxxxxxx>, Patrick McHardy <kaber@xxxxxxxxx> wrote: > Kris Op de Beeck wrote: >> * Problem: >> The replacing of the destination IP address doesn't occur always. I've got > a PC on which I run a program which retrieves web pages of 30 modems which > all have the same IP address. In order to do this I created the > configuration as listed below. For the program the IP addresses will be > 10.9.9.1 to 10.9.9.30. Those will be send out on a specific VLAN and the IP > address will be replaced by 192.168.1.1. A number of times I get a 'no route > to host' for those web pages, this happens sporadically. If I start looking > at the ARP messages, I see that when it goes wrong an ARP message is send out > for an 10.9.9.x address which shouldn't be the case. >> On an older setup I didn't had this problem, so I downgraded the kernel > version from 2.6.22-14-generic to 2.6.17-12-generic on the setup where I had the > problem. >> With this downgraded kernel the problem didn't occur anymore. >> The distro is Ubuntu. An upgrade to Ubuntu 8.04 which has kernel 2.6.24 > didn't solve the problem. >> >> * Setup: >> - On which I have the problem: >> PC -> Vlan enabled ethernet switch -> 30 modems with the same IP address. >> >> - Simplified: >> PC -> PC >> for 1 port use the configuration as mentioned below. For the other port use > 192.168.1.1 as IP address for each VLAN. >> Then you can just ping 10.9.9.x to test. >> I have not tried this. >> >> * Perl script to generate configure script: >> !/usr/bin/perl -w >> >> my $vlan = 100; >> my $modem = 1; >> my $subip = 2; >> for (my $modem = 1;$modem <= 30;$modem++) { >> print "echo \"------------$vlan--------------------\"\n"; >> print "vconfig add eth2 $vlan\n"; >> print "ifconfig eth2.$vlan 192.168.1.$subip\n"; >> print "route del -net 192.168.1.0/24\n"; >> print "route add -host 10.9.9.$modem eth2.$vlan\n"; >> print "iptables -t nat -A OUTPUT -o eth2.$vlan -j DNAT --to 192.168.1.1\n"; >> >> print "iptables -t mangle -N VLAN$vlan\n"; >> print "iptables -t mangle -F VLAN$vlan\n"; >> print "iptables -t mangle -A VLAN$vlan -j MARK --set-mark $vlan\n"; >> print "iptables -t mangle -A OUTPUT -o eth2.$vlan -j VLAN$vlan\n"; >> print "ip ro add table $vlan default dev eth2.$vlan\n"; >> print "ip ru add fwmark $vlan table $vlan\n"; >> print "ip ro fl ca\n"; >> $vlan++; >> $subip++; >> }; >> > > Please try loading ipt_LOG and executing > > "echo 255 >/proc/sys/net/netfilter/nf_conntrack_log_invalid" > > and see if something shows up in the ringbuffer. [ 917.584000] nf_ct_tcp: invalid SYNIN= OUT= SRC=192.168.1.23 DST=10.9.9.22 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=3257 DF PROTO=TCP SPT=40018 DPT=80 SEQ=1136088214 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A00025B1C0000000001030307) UID=1000 [ 918.800000] nf_ct_tcp: invalid SYNIN= OUT= SRC=192.168.1.22 DST=10.9.9.21 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=26411 DF PROTO=TCP SPT=47713 DPT=80 SEQ=1041054567 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A00025C4C0000000001030307) UID=1000 [ 921.800000] nf_ct_tcp: invalid SYNIN= OUT= SRC=192.168.1.22 DST=10.9.9.21 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=26412 DF PROTO=TCP SPT=47713 DPT=80 SEQ=1041054567 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A00025F3A0000000001030307) UID=1000 [ 924.204000] nf_ct_tcp: invalid SYNIN= OUT= SRC=192.168.1.30 DST=10.9.9.29 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=25744 DF PROTO=TCP SPT=52775 DPT=80 SEQ=2154890499 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A000261930000000001030307) UID=1000 [ 927.204000] nf_ct_tcp: invalid SYNIN= OUT= SRC=192.168.1.30 DST=10.9.9.29 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=25745 DF PROTO=TCP SPT=52775 DPT=80 SEQ=2154890499 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A000264810000000001030307) UID=1000 For those DST ip addresses I've got failures Newtec will be present at the following exhibitions : CommunicAsia, 17-20 June, Singapore, Booth 6B2-01 *** e-mail confidentiality footer *** This message and any attachments thereto are confidential. They may also be privileged or otherwise protected by work product immunity or other legal rules. If you have received it by mistake, please let us know by e-mail reply and delete it from your system; you may not copy this message or disclose its contents to anyone. E-mail transmission cannot be guaranteed to be secure or error free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or contain viruses. The sender therefore is in no way liable for any errors or omissions in the content of this message, which may arise as a result of e-mail transmission. If verification is required, please request a hard copy. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html