Eu tenho a solução!
O comando que eu executei era:
# route del -net 192.168.0.0 netmask 255.255.255.0 eth1
Depois desse comando minha: rede 0, rede 10 E rede 51 estava acessível.
Eu também editei /etc/sysctl.conf
e descomentei net.ipv4.ip_forward=1
antes, mas não tenho certeza se isso é necessário.
minhas configurações:
ifconfig -a
eth0 Link encap:Ethernet HWaddr 00:0c:29:e0:03:9c
inet addr:192.168.10.2 Bcast:192.168.10.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fee0:39c/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:53794 errors:0 dropped:0 overruns:0 frame:0
TX packets:53916 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:6812117 (6.8 MB) TX bytes:21573511 (21.5 MB)
eth0:1 Link encap:Ethernet HWaddr 00:0c:29:e0:03:9c
inet addr:192.168.10.10 Bcast:192.168.10.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
eth1 Link encap:Ethernet HWaddr 00:0c:29:e0:03:a6
inet addr:192.168.0.237 Bcast:192.168.0.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fee0:3a6/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:29845 errors:0 dropped:0 overruns:0 frame:0
TX packets:469 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:2555869 (2.5 MB) TX bytes:42872 (42.8 KB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:8157 errors:0 dropped:0 overruns:0 frame:0
TX packets:8157 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:624350 (624.3 KB) TX bytes:624350 (624.3 KB)
route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.51.0 192.168.0.1 255.255.255.0 UG 0 0 0 eth1
192.168.10.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
0.0.0.0 192.168.10.254 0.0.0.0 UG 0 0 0 eth0
0.0.0.0 192.168.10.254 0.0.0.0 UG 100 0 0 eth0
0.0.0.0 192.168.10.254 0.0.0.0 UG 100 0 0 eth0
/ etc / network / interfaces
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).
# The loopback network interface
auto lo
iface lo inet loopback
# The primary network interface
auto eth0
iface eth0 inet static
address 192.168.10.2
netmask 255.255.255.0
gateway 192.168.10.254
auto eth0:1
iface eth0:1 inet static
address 192.168.10.10
netmask 255.255.255.0
gateway 192.168.10.254
auto eth1
iface eth1 inet static
address 192.168.0.237
netmask 255.255.255.0
gateway 192.168.0.1
post-up route add -net 192.168.51.0 netmask 255.255.255.0 gw 192.168.0.1