Connection properties for XA datasources in JBoss EAP 6 are configured in XA properties tab, e.g. using the ServerName, DatabaseName and PortNumber properties. How to specify the SQL Server database instance name I want the data source to connect to?
In jtds I use the pattern: jdbc:jtds:sqlserver://@ServerName/@DatabaseName;instance=@InstanceName
Apparently the @InstanceName should be specified as a part of @ServerName, as follows:
@ServerName\\@InstanceName
Note the double backslash is necessary while using the Admin Console Add dialog (Properties tab) - it will be automatically converted to single backslash. If a single backslash is entered, it is not possible to add the property at all (there is no warning/error message showed though).