Thread: Eror with NAT?

i asked question few days ago but.. got no reply. maybe did'nt put enough information or something... i've gotten little closer problem.
have modem connected server through usb. have router connect server through ethernet. doing forward router (to monitor , control traffic). router internal network , modem external. modem (eth1) provides ip through dhcp , set router (eth0) static ip. set in interfaces file. once interfaces , have ip set, run script activates need make server nat capable. but.... not work. fails. if replace modem phones tethering (usb0) works. has modem. cannot find out modem doing wrong.

here information

ifconfig

code:

eth0      link encap:ethernet  hwaddr 00:30:67:41:0c:3a             inet addr:192.168.0.1  bcast:192.168.0.255  mask:255.255.255.0           inet6 addr: fe80::230:67ff:fe41:c3a/64 scope:link           broadcast running multicast  mtu:1500  metric:1           rx packets:26786 errors:0 dropped:0 overruns:0 frame:0           tx packets:6694 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            rx bytes:3523402 (3.5 mb)  tx bytes:2967175 (2.9 mb)  eth1      link encap:ethernet  hwaddr 00:14:04:e7:24:b7             inet addr:72.191.165.30  bcast:255.255.255.255  mask:255.255.248.0           broadcast running multicast  mtu:576  metric:1           rx packets:297270 errors:0 dropped:0 overruns:0 frame:0           tx packets:136021 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            rx bytes:149936774 (149.9 mb)  tx bytes:9342291 (9.3 mb)  lo        link encap:local loopback             inet addr:127.0.0.1  mask:255.0.0.0           inet6 addr: ::1/128 scope:host           loopback running  mtu:16436  metric:1           rx packets:264 errors:0 dropped:0 overruns:0 frame:0           tx packets:264 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:0            rx bytes:21396 (21.3 kb)  tx bytes:21396 (21.3 kb)

the nat script

code:

echo -e "\n\nloading simple rc.firewall-iptables version $fwver..\n" depmod=/sbin/depmod modprobe=/sbin/modprobe  extif="eth1" intif="eth0" #intif2="eth0" echo "   external interface:  $extif" echo "   internal interface:  $intif"  #====================================================================== #== no editing beyond line required initial masq testing ==  echo -en "   loading modules: " echo "  - verifying kernel modules ok" $depmod -a echo "----------------------------------------------------------------------" echo -en "ip_tables, " $modprobe ip_tables echo -en "nf_conntrack, "  $modprobe nf_conntrack echo -en "nf_conntrack_ftp, "  $modprobe nf_conntrack_ftp echo -en "nf_conntrack_irc, "  $modprobe nf_conntrack_irc echo -en "iptable_nat, " $modprobe iptable_nat echo -en "nf_nat_ftp, " $modprobe nf_nat_ftp echo "----------------------------------------------------------------------" echo -e "   done loading modules.\n" echo "   enabling forwarding.." echo "1" > /proc/sys/net/ipv4/ip_forward echo "   enabling dynamicaddr.." echo "1" > /proc/sys/net/ipv4/ip_dynaddr  echo "   clearing existing rules , setting default policy.."  iptables-restore <<-eof *nat -a postrouting -o "$extif" -j masquerade commit *filter :input accept [0:0] :forward drop [0:0] :output accept [0:0] -a forward -i "$extif" -o "$intif" -m conntrack --ctstate established,related -j accept  -a forward -i "$intif" -o "$extif" -j accept -a forward -j log commit eof  echo -e "\nrc.firewall-iptables v$fwver done.\n"

the problem looks fine... (it ping , through clent computer on router) when try connect web address hang about 3 minutes , times out.
server's internet connection works know not forwarding modems connection. blocking port 80 ip tables says forwarding ports.

iptables -l

code:

chain input (policy accept) target     prot opt source               destination           chain forward (policy drop) target     prot opt source               destination          accept      --  anywhere             anywhere             ctstate related,established accept      --  anywhere             anywhere             log         --  anywhere             anywhere             log level warning  chain output (policy accept) target     prot opt source               destination

aha! may have found issue here! after tcpdump noticed stange...

in quite few of lines!
14:04:51.422926 arp, reply chris-a770e3.local is-at 00:30:67:41:0c:3a (oui unknown), length 28
.................................................. .................................................. .....(oui unknown).................

after googling baisically saying doesnt know send packet to. seems reason why cant work, beacause being droped! now.. next issue... do knoledge?

, not line.. giving error router , server. server being chris-a770e3.local , router being 192.168.0.1
leads me believe server isnt correctly converting mac address during nat. there somewhere can adjust this?

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