As described in Section 2.5, “Good Practice: Check the Oracle VM Manager Start Up State”, it is good practice to check the running status of Oracle VM Manager before making any subsequent API calls. This is achieved by submitting a GET query to the following URI:

https://hostname:port/ovm/core/wsapi/rest/Manager

The running status of Oracle VM Manager is indicated by the managerRunState property, returned in the response to this query.

Your code should loop to repeat this query until the value of the managerRunState property is equivalent to 'RUNNING', before allowing any further operations.