🔰 Create a network Topology Setup in such a way

Shubham Jangid

4 min readJan 5, 2021

so that System A can ping to two Systems
System B and System C but both these systems should not be pinging each other without using any security rule
e.g firewall etc.

For archive this high level setup we need to configure all of three systems.

So lets Start with system A:-

First we check the IP address and routing rules of system A which is provided by the system By default.

ifconfig ens160
route -n

Now we change the IP address of System A :-
ifconfig ens160 192.168.80.1/24

Here ens160 is my OS network card name and 192.168.80.1 is the New IP of this system /24 is for set the netmask value as “255.255.255.0”

We also need to add the new routing rule for this system for this we use CMD:-

route add -net 192.168.80.0/30 ens160

This route rule say that, System A only connect to other system with the IP range “192.168.80.1” to “192.168.80.3”

Here IP “192.168.80.0” is reserved for the Network Name.

/30 means that the netmask value for this network is “255.255.255.252”

Now Start Configuring the system B:-

First we check the IP address and routing rules of system B which is provided by the system By default.

ifconfig ens160
route -n

Now we change the IP address of System B:-
ifconfig ens160 192.168.80.2/24

Here ens160 is my OS network card name and 192.168.80.2 is the New IP of this system /24 is for set the netmask value as “255.255.255.0”

We also need to add the new routing rule for this system for this we use CMD:-

route add -net 192.168.80.0/31 ens160

This route rule say that, System A only connect to other system, which system IP is “192.168.80.1” and As we configured above this is the IP of System A.

/31 means that the netmask value for this network is “255.255.255.254”

Here we have “No” connectivity to other system rather than A.

Now Start Configuring the system C:-

First we check the IP address and routing rules of system C which is provided by the system By default.

ifconfig ens160
route -n

Now we change the IP address of System C:-
ifconfig ens160 192.168.80.3/24

Here ens160 is my OS network card name and 192.168.80.3 is the New IP of this system /24 is for set the netmask value as “255.255.255.0”

We also need to add the new routing rule for this system for this we use CMD:-

route add -net 192.168.80.0/31 ens160

This route rule say that, System Conly connect to other system, which system IP is “192.168.80.1” and As we configured above this is the IP of System A.

/31 means that the netmask value for this network is “255.255.255.254”

Here we have “No” connectivity to other system rather than A.

Now We Start pining The System:-

→ Now we try to ping system A to system B