Hi, Some notes on routing philosophy with linux. Suposse you have an IP on eth0, say A.B.C.D, and a default gateway A.B.C.E using: ip ad ad A.B.C.D/24 dev eth0 ip rou ad default via A.B.C.E All is OK and working. Suposse now you define a routing table Test and do: ip rou ad default via A.B.C.E table Test ip rule add from A.B.C.D table Test ip rou flu cac All is still OK, then you put an INVALID default gateway A.B.C.Y (this IP is not a gateway, in fact it is no associated to any computer): ip rou del default ip rou ad default via A.B.C.Y Then, you telnet some_IP, IT WORKS as pakets are routed USING table Test. If you do: ip rou get some_IP it says: some_IP via A.B.C.Y dev eth0 src A.B.C.D Is this a correct response???? If you issue: ip rou get some_IP from A.B.C.D it says the coreect answer: some_IP from A.B.C.D via A.B.C.E dev eth0 In fact if you do: ip rou del default then telnet some_IP it says: Trying some_IP... telnet: connect to address some_IP: Network is unreachable but this is not true ... as default gw of main table is never used. So it seems you have to stat some (even invalid) default gateway to achieve routing. Any comment??
