When the vmware-system-user password has been lost or forgotten and the current password cannot be retrieved from the VCF Fleet Manager appliance, the steps in this KB can be used to reset the password.
Log in to the management domain vCenter's vSphere UI
Open a console to the appliance VM
Restart the appliance VM
In the Appliance VM console window, type 'e' when the Photon splash screen is seen to edit the Grub boot menu
Append the following to the line that starts with linux /$photon_linux...
rw init=/bin/bash
Press CTRL+X or F10 to boot
Change the vmware-system-user password
passwd vmware-system-user
Unlock the vmware-system-user account
faillock --reset
Reboot the appliance VM
reboot -f
Repeat steps 2 through 8 for the remaining VCF Identity Broker appliance VMs
Allow 5-10 minutes for VCF Identity Broker services to fully start
Log in to VCF Operations UI and navigate to Fleet Management > Passwords > VCF Management
Check VCF Identity Broker in the Filters and click Apply
Select the Radio button next to the first vmware-system-user entry and click Remediate Password
Enter the password that was set in Step 7 in the Password and Confirm Password fields then click Remediate Password
Repeat steps 13 through 15 for the remaining vmware-system-user entries
Navigate to Fleet Management > Lifecycle VCF Management > Components and click Manage next to identity broker
Click Trigger Inventory Sync and then click Submit
Verify the inventory sync completes successfully