dhcp-namespaces-1

==terminal 1===
ip netns add space-a
ip netns add space-b
ip link add veth0 type veth peer name veth1
ip link set veth1 netns space-a
ip link add veth2 type veth peer name veth3
ip link set veth3 netns space-b
ifconfig veth0 10.0.0.0/31 up
ifconfig veth2 10.0.0.2/31 up
route add -host 10.0.0.1 dev veth0
route add -host 10.0.0.3 dev veth2
dnsmasq --no-daemon --dhcp-range=10.0.0.1,10.0.0.1,4h --dhcp-range=10.0.0.3,10.0.0.3,4h --log-dhcp --dhcp-leasefile=/tmp/test.lease

===terminal 2===
ip netns exec space-a ifconfig veth1 up
ip netns exec space-a dhclient -v veth1
ip netns exec space-a ping 8.8.8.8 #assuming you have masquerade from 10.0.0.1

===terminal 3===
ip netns exec space-b ifconfig veth3 up
ip netns exec space-b dhclient -v veth3
ip netns exec space-b ping 8.8.8.8 #assuming you have masquerade from 10.0.0.3