Backup attempts of a virtual machine through the agentless backup feature fail with, "Critical backup failure: HTTP: Could not connect to host," or "Cannot connect to the host \- aborting backup."
- Datto SIRIS
- Agentless Backups
- The Datto appliance cannot reach the host hypervisor.
- Verify connectivity between the Datto appliance and the hypervisor, and that networking requirements are satisfied as defined in the SIRIS, ALTO and DNAS Networking & Bandwidth Requirements article.
- Restart the vCenter service using the vSphere console.