Route between two routers

Question

This is the topology I'm working with.

I'm able to ping from VPC_LAN_Ato VPC_LAN_B and trying now to ping from those lans to Router_2_Cisco.

Here are the configurations for these 4 devices:

VPC_LAN_A:

ip 192.168.10.1/25 192.168.10.10

VPC_LAN_B:

ip 192.168.10.129/26 192.168.10.130

Router_1_Mikrotik:

ip address

add address=192.168.10.10/25 interface=ether1

add address=192.168.10.130/26 interface=ether2

ip route

add gateway=192.168.10.161

Router_2_Cisco:

interface FastEthernet0/0

ip address 192.168.10.161 255.255.255.252

no shutdown

I've looked for it on the internet and I know I have to do routing between the two routers but can't seem to find the right way to do it. Any explanation would be great.

Answer 1

First of all, you need to know that routers are aware of interfaces to which they are connected.

https://geek-university.com/ccna/directly-connected-routes/

So if you want to ping 192.168.10.161 from VPC_LAN_A, then the following happens:

• VPC_LAN_A will send the packet to its default gateway, which is R1's e0 interface

• R1 will check packet's layer 3 and will see, that the dest address is 192.168.10.161

• now it will look to its routing table and will see that this address is directly connected to interface e3

• so it will send the packet to R2

• R2 receives this ICMP message and wants to ping back

• but R2 has no idea what's the next hop for 192.168.10.1 (VPC_LAN_A), so it drops the packet

in other words, R2 does not know how to reach 192.168.10.1 or 192.168.10.129.

The simplest solution to this problem is to specify the next hop for these addresses on R2

https://www.cisco.com/c/en/us/support/docs/dial-access/floating-static-route/118263-technote-nexthop-00.html

The next hop for 192.168.10.1 or 192.168.10.129 is R1's e3 IP address. This is called a static routing.

Another way of solving this problem is to use a dynamic routing protocol, like RIP or OSPF.

Hope this helps.