documentation.md

what is namespace?

namespace is a powerful mechanism fo isolating resources and process within a single operating system.

imagine them as virtual containers housing separate environments where process have limited visibility

and interaction with the wider system. Linux has several types namespace. Like Mount, Network, UTS, Process, IPC etc

What is network namespace?

A network namespace acts as a separate virtual network environment within a single operating system. Imagine it as a ## self-contained network world, isolated from the host system's network while sharing the underlying hardware

Virtual Interface (veth)

A veth as a virtual Ethernet cable with two ends. Each end acts as a separate network interface, appearing like physical ## network adapters to processes residing within different network namespaces. When data is sent from one end, it's

automatically received by the other end within its respective namespace.

Linux Bridge

A Linux bridge as a virtual network switch. It connects multiple network interfaces (including physical and virtual ones ## like veth) and forwards data packets between them based on their destination addresses. This allows for more complex

network topologies within a single system.

Create two namespace and connect with veth

Step 1: first i create two namespace

sudo ip netns add black
sudo ip netns add white

Step 2: then i create virtual ethernet interface for link two namespace

sudo ip link add veth-black type peer name veth-white

Step 3: then set each veth to each namespace interface

sudo ip link set veth-black netns black
sudo ip link set veth-white netns white

Step 4: now i assign ip address to each namespace veth interface

sudo ip netns exec black ip addr add 192.168.15.1/24 dev veth-black
sudo ip netns exec white ip addr add 192.168.15.2/24 dev veth-white

Step 5: now i up each namespace veth interface

sudo ip netns exec black ip link set veth-black up
sudo ip netns exec white ip link set veth-white up

Step 6: now i test the connection with ping

sudo ip netns exec black ping -c 2 192.168.15.2
sudp ip netns exec white ping -c 2 192.168.15.1

create two namespace and connect with linux bridge

Step 1: first i create two namespace

sudo ip netns add black
sudo ip netns add white

Step 2: create linux bridge

sudo ip link add v-net-0 type bridge

Step 3: bring linux bridge up

sudp ip link set dev v-net-0 up

Step 4: now i create virtual ethernet (veth) for connect each namespace with linux bridge

sudo ip link add veth-black type veth peer name veth-black-br
sudo ip link add veth-white type veth peer name veth-white-br

Step 5: now attach veth with each namespace

sudo ip link set veth-black netns black
sudo ip link set veth-white netns white

Step 6: now attach veth with linux bridge for each namespace

sudo ip link set veth-black-br master v-net-0
sudo ip link set veth-white-br master v-net-0

Step 7: now i assing ip address for each namespace veth interface

sudo ip netns exec black ip addr add 192.168.15.1/24 dev veth-black
sudo ip netns exec white ip addr add 192.168.15.2/24 dev veth-white

Step 8: now i need to bring up each veth for each namespace

sudo ip netns exec black ip link set veth-black up
sudo ip netns exec white ip link set veth-white up

Step 9: now test connectivity

sudo ip netns exec black ping -c 2 192.168.15.2
sudo ip netns exec white ping -c 2 192.168.15.1