Re: Ip forwarding

Pascal Hambourg wrote:
Sambo a écrit :


Changing net/ipv4/ip_forward also affects net/ipv4/conf/*/forwarding.


little correction to this ??filter files contain 0.


Filter files ? What do you mean ?


/proc/sys/net/ipv4/conf/eth0/rpfilter
/proc/sys/net/ipv4/conf/eth1/rpfilter


I hope by "sent to it" you mean "reaching it" as opposed to "addressed to it", or is packet wrapping involved here.


I mean "addressed to it" at link layer (MAC address). Packets that are meant to be forwarded by a router must be sent to its MAC address on the link. This MAC address is obtained by doing an ARP query to the router's local IP address, which is the gateway address in the routing table.

Oh , sorry, that makes sense.



Why 192.168.0.9 ? According to your diagram, comp2's eth1 address is 192.168.0.8.


Yes, interchanged the 8 and 9 the first time.

The interface column contains the output interface for a given destination. The gateway column optionnally contains the address of the next hop router if the destination is not directly reachable on the network attached to the output interface. The gateway address must be directly reachable on the network attached to the output interface.

"*" or 0.0.0.0 as the gateway means that the destination is directly reachable on the network attached to the output interface. In this case you can consider that the next hop address is equal to the destination address.

In both cases the packet is sent on the link to the next hop MAC address.

Yes, must be MAC addressed to somebody in the neighbourhood, carrying any INET destination address, GOT IT.
.

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