Using Microsoft® SQL Server as a database backend

Create a database on your backend, plus a user (and assign it the db_owner role)

In %RDECK_BASE%\server\config\rundeck-config.properties, set the following:

dataSource.driverClassName = com.microsoft.sqlserver.jdbc.SQLServerDriver
dataSource.url = jdbc:sqlserver://mssql.rundeck.local;DatabaseName=rundeck
dataSource.username = rundeckuser
dataSource.password = rundeckpassword