vCenter has detected an error with the DAS (Distributed Availability Service) agent service in this vSphere HA cluster.
There is a HA error on the host.
The event HostDasOk from the vSphere API will automatically close this alert and reset cluster state to Green.
Check the status of the HA agent on the host, check network communications between host(s) and vCenter Server, check shared storage configuration and availability.
Refer to the VMware Online Documentation for more information.