Installing the software switch

Requirements

The network interface cards you’re planning to use for the data plane need to support hardware timestamping. To check this, run sudo ethtool -T <NIC-NAME> and look for the hardware-transmit and hardware receive capabilities.

1. Install the programs

(If you’ve already done this step to install the CNC, then you can skip to the next step)

On the Debian device you want to run the software switch on, simply clone/copy the project repository onto the device and (from the repository’s root) run:

sudo ./tools/setup-on-debian.sh

DO NOT RUN THIS SCRIPT TWICE. If you’ve already installed the CNC, do not run this script again, just proceed with the next step.

If you don’t have permission, run chmod +x ./tools/setup-on-debian.sh and then try again.

The script will automatically fetch the necessary dependencies and build the executables.

2. Disable default NTP

Disable the system’s default NTP service, it might interfere with our own clock synchronization

sudo timedatectl set-ntp false

3. Add NTP servers

This step is only necessary if you want/need to use custom NTP servers, for example if your network’s firewall blocks NTP packets. Advanced users that use a custom method of time synchronization, so that NTP won’t be used on this device, can skip this step as well.

Create a file in /etc/chrony/sources.d/ with the file name ending with .sources. Then, for a default NTP configuration, add as many server <NTP-SERVER-ADDRESS> iburst directives as needed, one directive per line, and the file must have a trailing newline character at the end.

For example, if you are inside the network of the Universität Stuttgart, which blocks NTP servers outside the network, this would be the example content of the file /etc/chrony/sources.d/uni-stuttgart-ntp.sources:

server time1.uni-stuttgart.de iburst
server time2.uni-stuttgart.de iburst
server time3.uni-stuttgart.de iburst

Don’t forget the trailing newline character!
For more advanced NTP configurations, check the chrony.conf documentation, since instead of server directives you can also use pool and peer directives in this file.

4. Set password

The default NETCONF password is private, you shouldn’t leave it like this. Use sudo passwd netconf-api to change it to something more secure. You will need to specify this password in the inventory.json file when you install the CNC!