This is less of a LinuxCNC issue and more of a Linux issue. I am selling my longtime linuxCNC machine and decided to change the computer name and password to the new buyers request. (Building a new machine)
I first did a password change using: passwd
Then I did a hostname change using: hostnamectl
I then verified the hostname had been changed and restarted the computer. Once I restart I can see the hostname changed on the login in screen, but it won't accept any combo of new or old login information. So I can't get into the system. Any ideas on what I can do to get in? I did take a backup of my config files before I did any of this, so its not the end of the work to re-install everything and drop the configs back in.
Boot with a live usb system, mount the hard drive and edit /etc/shadow and remove password from the user. Then umount, boot & login without password.
Depending on the linux distribution, you may already have a resque/repair boot option which should give a root shell to fix things.
