If you are locked out of your Ubuntu instance and have lost access to the root account, you need to boot into single-user mode and reset the root password. These steps apply to Ubuntu 18.x, 19.x, 20.x, and 21.x.
Click the Server Restart icon in the Vultr customer portal.
Open the web console.
You can also reboot the server from inside the web console. See the Web Console FAQ for more information.
As the system boots, press ESC to bring up the GRUB boot prompt. The prompt happens early in the boot process. If you miss the prompt, you need to restart the server from the control panel and try again.
init=/bin/bashto the end of the line.
mount -o remount,rw /to mount the system volume.
passwdand follow the prompts to change the root password.
Reboot the server.
# exec /sbin/init