Username should be: api
Password: < your-api-key >
In the Endpoint Context Server Actions config:
Action
URL:
/messages
Header:
Content-Type application/x-www-form-urlencoded
Content:
Notice that the contents are URL encoded with the exception of dynamic ClearPass variables (those will be encoded after they are replaced).
from=Aruba+Boston+%3Cno-reply%40arubaboston.com%3E&to=%{Endpoint:Email}&subject=Device+Quarantined&text=Your+device+has+been+blocked+from+the+network+due+to+abuse.+Please+contact+the+help+desk%2E
Here is a good URL encoding tool: https://www.freeformatter.com/url-encoder.html