>Почитай доки по tcpdump. Он покажет какие пакеты откуда/куда идут.
>Покажи route -n
>ifconfig до и после поднятия PPPoE
>и на всякий случай arp -n Посмотрю.
root@router:~# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
213.132.64.197 0.0.0.0 255.255.255.255 UH 0 0 0 ppp0
192.168.144.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
10.0.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.152.0 0.0.0.0 255.255.252.0 U 0 0 0 eth1
192.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 eth1
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 0.0.0.0 0.0.0.0 U 0 0 0 ppp0
root@router:~# ifconfig
eth0 Link encap:Ethernet HWaddr 00:04:79:67:F6:C1
inet addr:10.0.0.1 Bcast:10.0.0.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:53447 errors:0 dropped:0 overruns:0 frame:0
TX packets:50630 errors:0 dropped:0 overruns:0 carrier:369
collisions:0 txqueuelen:1000
RX bytes:51706119 (49.3 Mb) TX bytes:13706719 (13.0 Mb)
Interrupt:9 Base address:0x6200
eth1 Link encap:Ethernet HWaddr 00:80:48:21:8B:AA
inet addr:192.168.152.22 Bcast:192.168.155.255 Mask:255.255.252.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:11786210 errors:0 dropped:0 overruns:0 frame:0
TX packets:11962256 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1920349469 (1831.3 Mb) TX bytes:2287235668 (2181.2 Mb)
Interrupt:11 Base address:0x6000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:404603 errors:0 dropped:0 overruns:0 frame:0
TX packets:404603 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:201114129 (191.7 Mb) TX bytes:201114129 (191.7 Mb)
ppp0 Link encap:Point-to-Point Protocol
inet addr:213.132.74.44 P-t-P:213.132.64.197 Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1492 Metric:1
RX packets:1435 errors:0 dropped:0 overruns:0 frame:0
TX packets:1691 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:3
RX bytes:688624 (672.4 Kb) TX bytes:468734 (457.7 Kb)
root@router:~# arp -n
Address HWtype HWaddress Flags Mask Iface
192.168.155.39 ether 00:04:61:A2:09:F4 CM eth1
10.0.0.2 ether 00:11:80:15:F3:F5 C eth0
192.168.152.100 ether 00:11:D8:90:17:A8 CM eth1
192.168.155.81 ether 00:16:EC:07:59:7E CM eth1
До поднятия PPPoE
root@router:~# ifconfig
eth0 Link encap:Ethernet HWaddr 00:04:79:67:F6:C1
inet addr:10.0.0.1 Bcast:10.0.0.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:53447 errors:0 dropped:0 overruns:0 frame:0
TX packets:50630 errors:0 dropped:0 overruns:0 carrier:369
collisions:0 txqueuelen:1000
RX bytes:51706119 (49.3 Mb) TX bytes:13706719 (13.0 Mb)
Interrupt:9 Base address:0x6200
eth1 Link encap:Ethernet HWaddr 00:80:48:21:8B:AA
inet addr:192.168.152.22 Bcast:192.168.155.255 Mask:255.255.252.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:11786210 errors:0 dropped:0 overruns:0 frame:0
TX packets:11962256 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1920349469 (1831.3 Mb) TX bytes:2287235668 (2181.2 Mb)
Interrupt:11 Base address:0x6000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:404605 errors:0 dropped:0 overruns:0 frame:0
TX packets:404605 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:201114229 (191.7 Mb) TX bytes:201114229 (191.7 Mb)
Slackware 10.2 (Kernel - 2.4.31)