I am having a hard time getting multiple User Profile Applications working in a single farm. We would like to have our staff in one web application / user profile application and our students in another. Everything I read says that you can have muliptle UPA in a single farm. When I create the first UPA MySites are created via Self Service when a user accesses https://staff.xyz.org. It appears to be fully functional with a single UPA. As soon as I create the second UPA things go bad. If all I have done is created the second UPA the first instance is still fully functional but the second gives errors right away. First it appears that the Web Application account for the second instance wants to have access to the content databases on the first instance. This is discovered in not being able to access the url https://students.xyz.org and receiving a correlation id. If I give it was it is wanting the page will then give an access denied message as though I do not have permissions to access the site even though Self Service is enabled and allow users are allowed to create profiles. If I setup a trust between the two hosts then the page will load but it does not redirect the user to the correct location on https://staff.xyz.org it will still say https://student.xyz.org. Even worse with the trust in place is that the first instance will now redirect to the second even if the user accessing the page has a profile in the first instance. If I remove the trust then everything works for the first instance again. Trying to use the Audiances does not seem to help since I have the users in different OUs. Creating an audiance for staff when the student UPA does not know of those accounts because it does not look at those OUs renders the audiance empty even if I create a OU for sharepoint groups so that both services could be aware of the groups (which does work they are just empty when compiled). I read that by default if you do not setup the trust then a user should be able to create a profile in each UPA and have two "MySites" essentially. No matter when I try I cannot get a single profile to create in the second instance even if the user accessing the site does not have an existing profile else where in the farm. I have delete and recreated these several times but it does not seem to change the outcome. Why does the second instance want access to the first instances content databases? As you will see below I have tried to separate everything as much as possible and met the requirement to run the sync instance on different servers. Both instance start fine and sync fine it is just something about creating site collections that is broken and the redirecting to the correct web application when the two trust eachother.
Web Application (Staff)
Web App = staff.xyz.orgAccount = SP15WEBSTAFFContent Database = SP15_WEBSTAFFCD01
Application Pool = MySites Staff
Site Collection = / My Sites Host
Profile Service = User Profile Service Application - Staff
Account = SP15SVCUPSTAFF
Profile DB = SP15_SVCAPPUPPROFILESTAFF
Sync DB = SP15_SVCAPPUPSYNCSTAFF
Social DB = SP15_SVCAPPUPSOCIALSTAFF
Instance Runs On = SP15APP01
Web Application (Student)
Web App = student.xyz.orgAccount = SP15WEBSTUDENTContent Database = SP15_WEBSTUDENTCD01
Application Pool = MySites Student
Site Collection = / My Sites Host
Profile Service = User Profile Service Application - Student
Account = SP15SVCUPSTUDENT
Profile DB = SP15_SVCAPPUPPROFILESTUDENT
Sync DB = SP15_SVCAPPUPSYNCSTUDENT
Social DB = SP15_SVCAPPUPSOCIALSTUDENT
Instance Runs On = SP15APP02