Introduction to Linux namespaces – Part 5: NET

Following the previous post on PID namespace (Restart process numbering to “1”), would like to go further and fly eve closer to full-featured VMs ? Great ! The two last posts of this series will precisely focus on this. Isolate network interfaces with the “NET” namespace (Yes, really) and user/group identifier for even more transparency. If you haven’t done so already, I encourage you to read the first post of this series for an introduction to linux namespace isolation mechanism.

[EDIT 2014-01-08] A Chinese translation of this post is available here

For once we won’t start with the addition of the “CLONE_NEWNET” flag to the “clone” syscall. I keep it for later. For now, IMHO, the best way to get started with this namespace is the incredibly mighty “iproute2” net-admin swiss army knife. If you don’t have it (yet) I highly encourage you to install it. Nonetheless, if don’t want to / can’t, you may as well skip the explanation part and go straight to the full code sample.

First, let’s see what network interfaces we have at the moment: