I always hate it when you can’t login into a system anymore because you either don’t know the root password anymore or the system is not able to log you in.
VCSA 6.5 is built on top of Photon OS, so can’t use the same standard procedure for Debian, Ubuntu or RedHat. It’s still very simple to reset the root password.
The first thing to do is to restart your vCenter appliance and wait for the Photon OS Splash screen during boot.
Hit the letter e to enter the boot menu.
Then change to the GNU GRUB boot menu editor and hit enter.
Next is to add the following string to the line that starts with linux: rw init=/bin/bash
Hit the F10 function key to boot the changed entry.
Reset the root password
To reset the root password, please follow these steps:
passwd
then enter a strong password twice and remember it.
umount /
reboot -f
It is important to add the -f behind the reboot.