Originally Posted by macemoneta
You are trying to statically assign the same IP address to multiple active Ethernet interfaces at the same time. This won't work - you will generate an ARP storm (each interface claiming to associate its MAC with the IP).
"(for some reason)" - If you tell us what you are trying to accomplish, we may be able to help you.
One reason is to increase the bandwidth of a server equipped with two full duplex interfaces which are on the same subnet.
I plan to do:
ip route del default
route add default gw 172.20.11.10 dev eth1
route add default gw 172.20.11.10 dev eth0
ip route add 172.20.11.0/24 dev eth0 table 2
ip route add 0/0 via 172.20.11.10 dev eth0 table 2
ip rule add from 172.20.11.242 table 2
ip rule add to 172.20.11.242 table 2
ip route add 172.20.11.0/24 dev eth1 table 3
ip route add 0/0 via 172.20.11.10 dev eth1 table 3
ip rule add from 172.20.11.199 table 3
ip rule add to 172.20.11.199 table 3
echo 1 > /proc/sys/net/ipv4/conf/eth0/arp_filter
echo 1 > /proc/sys/net/ipv4/conf/eth1/arp_filter
However, "SIOCADDRT: Network is unreachable" error occurred.
# ip route
172.20.11.0/24 dev eth1 scope link
127.0.0.0/8 dev lo scope link
default via 172.20.11.10 dev eth1
# route add default gw 172.20.11.10 dev eth0
SIOCADDRT: Network is unreachable