Support for teachers working at multiple schools
ithin our MAT we have a number of schools each with their own MIS/SIS. For teachers that teach across more than one school, they'll therefore have more than one MIS/SIS staff record and hence more than one MIS/SIS ID. To prevent that staff member from having more than one AD User object (we have a single domain in a single forest for all schools) I set the SamAccountName within the MIS/SIS record for that staff member, and our custom PowerShell provisioning script tests for the presence of that username and if it exists knows not to create another AD user.
This local AD domain for all schools is then synced to our Office 365 Education tenant via Azure AD Connect. Knowing that School Data Sync requires the ID field of the student.csv and teacher.csv files to be unique, when I export the data from each school I add a suffix (via PowerShell) to the ID to ensure uniqueness. For example, let's say I have a staff member who teaches in two schools, on one MIS their ID is 24, on another MIS their ID is 35, my teacher.csv might look like this:
ID,School DfE Number,Username