We have found a bug in the RISPort API for CUCM version 18.104.22.16800-6 here are the details:
When sending a 'selectCmDevice' request to the /realtimeservice2/services/RISService70 URL we get a valid response but it contains zero device details.
When sending an identical request to the same URL for CUCM version 22.214.171.12400-2 we get a valid response that include the relevant device information.
I've attached a screenshot of two request/responses, the request/response on the left is to CUCM 11.5, the request/response on the right is to CUCM 11.0
The device names used are valid and if we send the request using 'selectCmDeviceExt' to UCM 11.5 using the same details it works fine, so the requests are correct, but the response is invalid. We have restarted the RIS Data Collector & RIS Soap API services with no effect.
I've been unable to reproduce this problem on my 126.96.36.19900-6 system. <selectCmDevice> request identical to yours returns expected live data.
I would suggest opening a ticket with DevNet developer support so they can investigate the Risport and web service logs to see if they can identify any issue in your particular system. As the request works with <selectCmDeviceEx> this appears very strange...
Thanks for checking David, we shall restart CUCM, hopefully it is a transient issue and not something we had seen before.