Hello, we typically have multiple new SDA switches created on regular basis. They have IP address and a hostname when provisioned but will not be added to a DNS server yet. Admins need access to these devices for configuration before they are available in DNS.  What is the best way to add these devices.

For existing switches which are in DNS , we add the hostname to Address Group and run IP Scan. The same address group is referenced in Managed Account smart rule. 

Q1. Add IP address to Address Group via API and trigger a scan . I think this will only add the system = IP address.
Q2. when the Address Group is scanned next , PS will know the hostname of it but will it update the same managed system with system = hostname (and IP = IP) ? or it will create two separate managed systems/assets.
Even if the system name gets updated with hostname , the managed account smart rule will not apply as it references the Address Group which does not have hostname of the system but only IP address. 
Q3. So should the API call add both hostname and IP  to Address Group , trigger scan that will find only IP as hostname is not resolved. Later when the scan runs again and DNS entry is added, it will either update existing system or create new system . Based on answer to Q2 I might end up with duplicate systems but the smart rule will work?  We need to scan these assets are we plan to scan these for further discovery at later stage. If we create managed system directly via API call we may not be able to scan it without creating duplicates