This is a very helpful article on pre-installing SQL Express on a SCCM 2012 Secondary server so you can customize the install to fit your needs.
Even after all of the tweaking noted in the article I still had issues.
I ran into these errors logged in \\CM12-Primary\%systemDrive%\ConfigMgrSetup.log
-CSql Error: Cannot find type data, cannot get a connection.
-*** [Microsoft][ODBC SQL Server Driver][DBNETLIB]SQL Server does not exist or access denied
However, even after enabling TCP/IP and setting the port to 1433 I still could not connect.
- I then validated that SQL Browser was running, but didn’t help.
- I used
netstat -ato validate that TCP 1433 was
listeningand UDP 1434 shows as
- I could connect to SQL locally using SQL Server Management Studio and SQLCMD, but I could not remotely UNTIL I added the port to the connection string (
It turns out that I didn’t set an exclusion in my SCCM Servers Firewall GPO for SQL Browser (UDP 1434). After adding the exclusion and running GPUpdate all is well.