Script to create two namespaces and connection between them

namespaces.sh

#Install Openvswitch on ubuntu
sudo apt-get install qemu-kvm libvirt-bin ubuntu-vm-builder bridge-utils
sudo apt-get install openvswitch-switch

#Create Namespace
sudo ip netns add mario
sudo ip netns add luigi

#Create virtual switch
sudo ovs-vsctl add-br my-switch
sudo ovs-vsctl show

#Setup veth and virtual switch
sudo ip link add mario-netns type veth peer name mario-ovs
sudo ip link set mario-netns netns mario
sudo ovs-vsctl add-port my-switch mario-ovs

sudo ip link add luigi-netns type veth peer name luigi-ovs
sudo ip link set luigi-netns netns luigi
sudo ovs-vsctl add-port my-switch luigi-ovs

#Bring up and assign IPs
sudo ip link set mario-ovs up
sudo ip link set luigi-ovs up
sudo ip netns exec mario ip link set dev lo up
sudo ip netns exec mario ip link set dev mario-netns up
sudo ip netns exec luigi ip link set dev lo up
sudo ip netns exec luigi ip link set dev luigi-netns up
sudo ip netns exec mario ip addr add 10.0.0.1/24 dev mario-netns
sudo ip netns exec luigi ip addr add 10.0.0.2/24 dev luigi-netns

#Test ping
sudo ip netns exec mario ping 10.0.0.2