Single User Mode - Password Recovery

Use single user mode to assist in troubleshooting system boot issues or for password recovery. To enter single user mode, follow the steps below.

A console connection is required to perform the following procedure.

  1. Boot the switch as soon as you see the GRUB menu.

                           GNU GRUB  version 2.02-cl3u3
     
     +----------------------------------------------------------------------------+
     |*Cumulus Linux GNU/Linux                                                    |
     | Advanced options for Cumulus Linux GNU/Linux                               |
     | ONIE                                                                       |
     |                                                                            |
     +----------------------------------------------------------------------------+     
    
  2. Use the ^ and v arrow keys to select Advanced options for Cumulus Linux GNU/Linux. A menu similar to the following should appear:

                           GNU GRUB  version 2.02-cl3u3
     
     +----------------------------------------------------------------------------+
     | Cumulus Linux GNU/Linux, with Linux 4.1.0-cl-7-amd64                       |
     |*Cumulus Linux GNU/Linux, with Linux 4.1.0-cl-7-amd64 (recovery mode)       |
     |                                                                            |
     +----------------------------------------------------------------------------+  
    
  3. Select Cumulus Linux GNU/Linux, with Linux 4.1.0-cl-7-amd64 (recovery mode).

  4. Press ctrl-x to reboot.

  5. After the system reboots, set a new root password. This is useful since the root user provides complete control over the switch, and providing a new password now helps in case the current password has been forgotten, which is a common problem.

    root@switch:~# passwd
    Enter new UNIX password:
    Retype new UNIX password:
    passwd: password updated successfully
    

    You may want to take this opportunity to reset the password for the cumulus account as well.

       root@switch:~# passwd cumulus
       Enter new UNIX password:
       Retype new UNIX password:
       passwd: password updated successfully
    
  6. Sync the /etc directory using btrfs, then reboot the system:

    root@switch:~# btrfs filesystem sync /etc
    root@switch:~# reboot -f
    Restarting the system.