Under Arch Linux, your network cards are sometimes named differently between two reboot. Configuring your network connection is hard if you don’t know if you card will be called eth0 or eth1.
A file /etc/udev/rules.d/75-persistent-net-generator.rules.optional can be used to tell udev to generate persistent network rules.
It’s very simple:
mv /etc/udev/rules.d/75-persistent-net-generator.rules.optional /etc/udev/rules.d/75-persistent-net-generator.rules
Reboot your system. A /etc/udev/rules.d/70-persistent-net.rules file has been generated. Now you can disable the generator:
mv /etc/udev/rules.d/75-persistent-net-generator.rules /etc/udev/rules.d/75-persistent-net-generator.rules.optional
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