Re: LAN to Lab subnet

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hiko wrote:

@vno

I don't disagree since I'm totally a newbie in networking but if a route needs to have a gateway in its own subnet, how do we route different subnets ?

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You have a router on each of those subnets.

Networking is kind of like a tree.

                                       (WAN)
                                         |
                                      router_1
                                         |
                                         |
                             +-----------+------------+
                             |                        |
                             |                        |
                      (192.168.1.0/24)         (192.168.2.0/24)
                             |                        |
                          router_2                 router_3
                             |                        |
                       (172.16.1.0/24)          (172.16.2.0/24)
                             |                        |
                  +----------+                        +------------+
                  |          |                        |            |
               host_a     host_b                   host_c       host_d
                  |          |                        |            |
                (.1.10)    (.1.11)                  (.2.100)     (.2.101)

Routing tables will look like this:

Router_1 (192.168.1.1 / 192.168.2.1)

0.0.0.0/0 via (WAN_Gateway), eth0
192.168.1.0/24 directly connected, eth1
192.168.2.0/24 directly connected, eth2
172.16.1.0/24 via 192.168.1.100, eth1
172.16.2.0/24 via 192.168.2.100, eth2

Router_2 (192.168.1.100)

0.0.0.0/0 via 192.168.1.1, eth0
192.168.1.0/24 directly connected, eth0
172.16.1.0/24 directly connected, eth1

Router_2 (192.168.1.100) (ALTERNATE, NO WAN ACCESS) 

192.168.1.0/24 directly connected, eth0
192.168.2.0/24 via 192.168.1.1, eth0
172.16.1.0/24 directly connected, eth1
172.16.2.0/24 via 192.168.1.1, eth0

Router_3 (192.168.2.100)

0.0.0.0/0 via 192.168.1.1, eth0
192.168.2.0/24 directly connected, eth0
172.16.2.0/24 directly connected, eth1

Router_3 (192.168.2.100) (ALTERNATE, NO WAN ACCESS)

192.168.2.0/24 directly connected, eth0
192.168.1.0/24 via 192.168.1.1, eth0
172.16.2.0/24 directly connected, eth1
172.16.1.0/24 via 192.168.1.1, eth0

 Hosts A, B

0.0.0.0 via 172.16.1.1, eth0
172.16.1.0/24 directly connected, eth0

Hosts C, D 

0.0.0.0 via 172.16.1.1, eth0
172.16.1.0/24 directly connected, eth0

You could also give fuller routing tables to the hosts, but I'm getting tired of writing them (they'd look similar to the "alternate" entries for the routers)

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hiko wrote:

 

Once again maybe it's a crazy setup since I don't know a lot in networking but it was working fairly well. I never really had the need of being able to communicate from the LAN to the LAB but now that I need it my setup looks to be incompatible.

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 Nah, the setup should work fine, you've just got routing messed up somewhere.