From the dmesg command, you can see that the device got renamed during the system boot.
$ dmesg | grep -i eth
To get an ethX back, edit the grub file.
$ sudo nano /etc/default/grub
Look for “GRUB_CMDLINE_LINUX
” and add the following”net.ifnames=0 biosdevname=0
“.
From:
GRUB_CMDLINE_LINUX=""
To:
GRUB_CMDLINE_LINUX="net.ifnames=0 biosdevname=0"
Generate a new grub file using the following command.
$ sudo grub-mkconfig -o /boot/grub/grub.cfg