Hovering over the Virtual Machine/Application backup status icon shows backup Consistency as crash-consistent or application-consistent.
When you perform SQL application backups from the Hycu Applications view, application consistency is ensured by Hycu remotely without need for Nutanix Guest Tools (NGT) or any other agents installed on the client system.
For other backups, VSS-based application consistency can be achieved using Nutanix Guest Tools (NGT) which need to be installed and configured on the client system. Therefore, not having NGT installed and configured on the client virtual machine will make Hycu fallback to crash-consistent snapshot.
Even if NGT tools are properly installed, there are number of different reasons why NGT tools could fail to achieve VSS application consistency. Prism will report a warning in these cases and this needs to be further troubleshooted on Nutanix. For detailed information about installing and configuring NGT, see Nutanix documentation.