# Network namespace ###### tags: `Docker` ## previously on namespace Namespace is a important technology of containerize virtualization like docker. Since NTU smartNIC project, I have to check LAN port usage on the same server, so I need to separate the testing LAN port to different namespace and ping from one to the other ## sop ```bash= # create namespace ip netns add net0 # ip netns add [name_of_new_namespace] ip netns add net1 # assign interface to namespace ip link set dev enp175s0 netns net0 # ip link set dev [LAN_interface_name] netns [name_of_interface] ip link set dev rename10 netns net1 ``` ```bash= # terminal 1 # enter into namespace net0 ip netns exec net0 /bin/bash # set network interface up ifconfig enp175s0 up # set ip ifconfig enp175s0 172.172.172.1 ``` ```bash= # terminal 2 # enter into namespace net0 ip netns exec net1 /bin/bash # set network interface up ifconfig rename10 up # set ip ifconfig enp175s0 172.172.172.2 # ping ping 172.172.172.1 ``` After finishing test, close all terminals and open a new terminal, delete all netns which you created for testing, net interfaces are all back to host netns ```bash= ip netns del net0 ip netns del net1 ```