Should you need to troubleshoot at any stage, please always come back to this point first and verify if testparm shows the parameters you expect. To give you a warning from personal experience, try to just comment out the load printers parameter. If your 2.2.x system behaves like mine, you'll see this:

root# grep "load printers" /etc/samba/smb.conf
        #  load printers = Yes
        # This setting is commented out!!
 
root# testparm -v /etc/samba/smb.conf | egrep "(load printers)"
        load printers = Yes

I assumed that commenting out of this setting should prevent Samba from publishing my printers, but it still did. It took some time to figure out the reason. But I am no longer fooled ... at least not by this.

root# 

grep -A1 "load printers" /etc/samba/smb.conf

        load printers = No
        # The above setting is what I want!
        #  load printers = Yes
        # This setting is commented out!

root# 

testparm -s -v smb.conf.simpleprinting | egrep "(load printers)"

        load printers = No

Only when the parameter is explicitly set to load printers = No would Samba conform with my intentions. So, my strong advice is:

The following is the most minimal configuration file:

root# 

cat /etc/samba/smb.conf-minimal

        [printers]

This example should show that you can use testparm to test any Samba configuration file. Actually, we encourage you not to change your working system (unless you know exactly what you are doing). Don't rely on the assumption that changes will only take effect after you restart smbd! This is not the case. Samba rereads it every 60 seconds and on each new client connection. You might have to face changes for your production clients that you didn't intend to apply. You will now note a few more interesting things; testparm is useful to identify what the Samba print configuration would be if you used this minimalistic configuration. Here is what you can expect to find:

root# 

testparm -v smb.conf-minimal | egrep "(print|lpq|spool|driver|ports|[)"

 Processing section "[printers]"
 WARNING: [printers] service MUST be printable!
 No path in service printers - using /tmp

        lpq cache time = 10
        load printers = Yes
        printcap name = /etc/printcap
        disable spoolss = No
        enumports command =
        addprinter command =
        deleteprinter command =
        show add printer wizard = Yes
        os2 driver map =
        printer admin =
        min print space = 0
        max print jobs = 1000
        printable = No
        printing = bsd
        print command = lpr -r -P%p %s
        lpq command = lpq -P%p
        printer name =
        use client driver = No

 [printers]
        printable = Yes

testparm issued two warnings:

However, this was not fatal, and Samba will default to values that will work. Please, do not rely on this and do not use this example. This was included to encourage you to be careful to design and specify your setup to do precisely what you require. The outcome on your system may vary for some parameters given, since Samba may have been built with different compile-time options. Warning: do not put a comment sign at the end of a valid line. It will cause the parameter to be ignored (just as if you had put the comment sign at the front). At first I regarded this as a bug in my Samba versions. But the man page clearly says: Internal whitespace in a parameter value is retained verbatim. This means that a line consisting of, for example,

will regard the whole of the string after the = sign as the value you want to define. This is an invalid value that will be ignored, and a default value will be used in its place.