(vCenter Server Appliance) VCSA 6.5
First, shut down the VCSA and take a snapshot for any incident happen to restore from last snapshot.
1. Start the appliance up and press the space bar to freeze the GRUB menu. Note that you need to be somewhat quick here.
2. Press e to enable edit mode.
3. Append rw init=/bin/bash to the list of options as shown in SC:1
SC:1 – Setting the boot options in GRUB
4. Press F10 to reboot. The appliance will now boot up in bash or root shell.
5. Type passwd to change the root password. Type it twice and press Enter to confirm.
6. Optionally, you can unmount the file system using umount /
Changing the root password and unmounting the file system
7. Reboot the vCenter Server Appliance by running this command:
reboot -f
8. Confirm that you can access the vCenter Server Appliance using the new root password.
9. Remove the snapshot taken in Step 1 if applicable.