A VMware NSX Manager/Edge is deployed/created from the NSX-T UI.
A VMware NSX Manager/Edge is deployed in vCenter using an OVF, during the deployment, the GRUB password is not provided. The GRUB password is then set after deployment using the nsxcli command "set grub root user password <password>".
When you launch VMware NSX Manager/Edge VM console in vCenter, you will see the following GRUB alert displayed: