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Virtual Products: Critical backup failure: HTTP: Service Unavailable (Failed to connect to endpoint)



This article provides troubleshooting steps to resolve the error message "Critical backup failure: HTTP: Service Unavailable (Failed to connect to endpoint)."

Backup Error at 10:31am Tuesday August 9th
Critical backup failure: HTTP: Service Unavailable (Failed to connect to endpoint: [class Vmacore::Http::LocalServiceSpec:00000000026F6F70] _serverNamespace = /sdk _isRedirect = false _port = 8085).


You may encounter this error message when attempting to perform agentless backups of protected servers in a VMware vCenter environment. 

This error can indicate that the Datto appliance is unable to connect to your hypervisor on port 8085. This is the port used for SDK connections to vCenter. 


Open port 8085 so that the Datto device can reach your hypervisor, and then attempt a new backup.

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