Migrating to new interface names in Debian 9 Stretch
Upgrading from Debian 8 (Jessie) to Debian 9 (Stretch) will retain the old interface names (eth0, eth1). This was intentionally done to provide a path of least disruption when it came to upgrades. New installations will automatically use the new naming convention.If you’d rather migrate to the new interface names, remove the following file: /etc/systemd/network/99-default.link Then edit /etc/network/interfaces accordingly with the new interface name.