In order to allow you to run more than one tinc daemon on one computer, for instance if your computer is part of more than one VPN, you can assign a netname to your VPN. It is not required if you only run one tinc daemon, it doesn’t even have to be the same on all the nodes of your VPN, but it is recommended that you choose one anyway.
We will assume you use a netname throughout this document. This means that you call tinc with the -n argument, which will specify the netname.
The effect of this option is that tinc will set its configuration root to /etc/tinc/netname/, where netname is your argument to the -n option. You will also notice that log messages it appears in syslog as coming from tinc.netname, and on Linux, unless specified otherwise, the name of the virtual network interface will be the same as the network name.
However, it is not strictly necessary that you call tinc with the -n option. If you do not use it, the network name will just be empty, and tinc will look for files in /etc/tinc/ instead of /etc/tinc/netname/; the configuration file will then be /etc/tinc/tinc.conf, and the host configuration files are expected to be in /etc/tinc/hosts/.