routing in the different subnet

[imeikk]

hai, guys i have a question, does anybody knows how to configure the routing in different subnet for linux, can somebody help me ? and pls state ur answer with the command also

example:
A :10.10.10.56 -------router----------C: 10.200.15.9
B :10.10.10.57 -------router----------D: 10.200.15.10

how does the router works on the different subnet that allows the A to ping C and B to D
if possible through the router A also can ping D and B to C and vise versa

ur help is appreciated.

[likwid]

How the router 'works' is a long explanation that gets really low-level. For information on routing I suggest you google some cisco docs. To send packets destined for 10.200.15.9 through a router whose ip address is 10.10.10.253, you would type at a console:

route add 10.200.15.9 gw 10.10.10.253

If you needed to route all packets to the 10.200.15.x network through router 10.200.10.253, you would type:

route add -net 10.200.15.0/24 gw 10.10.10.253

Note that 10.10.10.253 (our ficticious router) must be reachable before these commands will work.

[imeikk]

thanks for the replied i got another question
A :10.10.10.56 -------router----------C: 10.200.15.9
B :10.10.10.57 -------router----------D: 10.200.15.10


Thanks for the replied,

i got a bit confused can u pls make it clear ?
the solution that u provided is it add it into the routing table then like below ?:
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.10.10.0 0.0.0.0 255.255.255.0 UGH 0 0 0 eth0
10.200.15.0 10.10.10.253 255.255.255.255 U 0 0 0 eth0
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0
0.0.0.0 0.0.0.0 0.0.0.0 U 0 0 0 eth0
0.0.0.0 0.0.0.0 0.0.0.0 U 0 0 0 eth0
0.0.0.0 10.10.10.1 0.0.0.0 UG 0 0 0 eth0

< pls correct me if my answer is wrong thanks >


and now i got another question is how is the adding host work, how it is function for ?
what is the different between add -net and add -host.

and does anybody knows how to calculate the netmask for the example above ?
is it possible ?
can u pls show me how is the netmask to be calculated ?

[likwid]

thanks for the replied i got another question
A :10.10.10.56 -------router----------C: 10.200.15.9
B :10.10.10.57 -------router----------D: 10.200.15.10


Thanks for the replied,

i got a bit confused can u pls make it clear ?
the solution that u provided is it add it into the routing table then like below ?:
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.10.10.0 0.0.0.0 255.255.255.0 UGH 0 0 0 eth0
10.200.15.0 10.10.10.253 255.255.255.255 U 0 0 0 eth0
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0
0.0.0.0 0.0.0.0 0.0.0.0 U 0 0 0 eth0
0.0.0.0 0.0.0.0 0.0.0.0 U 0 0 0 eth0
0.0.0.0 10.10.10.1 0.0.0.0 UG 0 0 0 eth0

< pls correct me if my answer is wrong thanks >

Your routing table is a little screwed up. The examples I provided for you were just that, examples; adding them could screw up your ability to access network resources. You already have a default gateway which is 10.10.10.1. This router should be configured properly, and would allow you access to other subnets.

and now i got another question is how is the adding host work, how it is function for ?
what is the different between add -net and add -host.

-net is to add a route to a network. -host adds a route to a specific host.

and does anybody knows how to calculate the netmask for the example above ?
is it possible ?
can u pls show me how is the netmask to be calculated ?

The netmask isn't really calculated from just the ip address. A netmask allows you to split a network into logical divisions. It is calculated based on the network address and the number of subnets to be within that network.

[imeikk]

thank q very much for ur information
ok now last more request from me can u pls using the example that i given from the begining?
can pls help me to set up the routing for this simple example?:
A :10.10.10.56 -------router----------C: 10.200.15.9
B :10.10.10.57 -------router----------D: 10.200.15.10

can u pls teach me on this ? pls state ur answer more details and easy to understand, and how does the routing table looks like? and what is the perfect answer that u will give to this solution ? as ur intelligent i think u must be able to do that right ?

ur reply very appreciated

[likwid]

Well I am not sure if you are asking how to configure the router, or how to configure the clients to pass information through the router. What exists at 10.10.10.1? Is it a Cisco box?

[imeikk]

yah i am asking for the how to configure the clients to pass information through the router.
could u pls help me ?10.10.10.1 is a gateway for the router so if i want to configure the clients pc wat should i do ? should i need to touch the router ?
could u pls teach me how ?

[likwid]

From the looks of your routing table, the clients are already configured to use a default gateway. If you're not reaching the other network through this gateway, then you have the router(s) configured wrong. I have very limited Cisco experience, haven't typed at an IOS terminal in a couple years... so I wouldn't be much help configuring it.