Why does the output of testparm differ from /etc/samba/smb.conf?

Question

This is the output of the [global] section of the /etc/samba/smb.conf of a random Synology NAS:

~# cat /etc/samba/smb.conf
[global]
        printcap name=cups
        winbind enum groups=yes
        include=/var/tmp/nginx/smb.netbios.aliases.conf
        min protocol=NT1
        security=user
        local master=no
        realm=*
        passdb backend=smbpasswd
        printing=cups
        max protocol=SMB3
        winbind enum users=yes
        load printers=yes
        workgroup=WORKGROUP

And this is the output of testparm, which is not identical although it says it loaded this configuration file:

# testparm -s
Load smb config files from /etc/samba/smb.conf
...
    [global]
            passdb backend = smbpasswd
            printcap name = cups
            realm = *
            security = USER
            server min protocol = NT1
            syno catia = Yes
            winbind enum groups = Yes
            winbind enum users = Yes
            winbind expand groups = 1
            notify:synotify = yes
            rpc_server:msftewds = embedded
            rpc_daemon:wspd = disabled
            fruit:locking = none
            rpc_server:mdssvc = embedded
            rpc_daemon:mdssd = disabled
            idmap config * : backend = syno
            include = /var/tmp/nginx/smb.netbios.aliases.conf
            smb encrypt = if_required
            strict sync = No

I know testparm has this option:

  -v, --verbose                   Show default options too

This explains for example that it does not return max protocol=SMB3, because it is already the default:

# testparm -s -v 2>&1 | grep "max protocol"
        client ipc max protocol = default
        client max protocol = default
        server max protocol = SMB3

But why for example does testparm return the values starting with rpc_ or the line fruit:locking = none. It is not set in the smb.conf. And I can't find it in any other file in /etc, too:

# grep -rIils fruit /etc
#

I mean, yes there is a setting in the GUI which seems to enable the vfs module "fruit", but why isn't it mentioned in any Samba Config file?

Answer 1

A default-value isn't some absolute value but relative. Meaning: what was compiled into the samba-binaries. Vendors can, at compile-time, define their own default values for some options.

Answer 2

This is very probably because synology takes the Samba source and adapts it to their needs, there a lots of smb.conf parameters on synology that do not exist in the standard Samba e.g. syno catia = Yes

Answer 3

I had this very confusing issue to where the interfaces parameter was overridden.

Using sudo testparm -s /etc/samba/smb.conf -v -d=10 I was able to read the detailed logs, and noticed that indeed the interfaces was getting overridden.

Using sudo net conf list I was able to see the parameter that I needed to remove:

To show only the interfaces parameter:

sudo net conf getparm global interfaces

Then do delete it: sudo net conf delparm global interfaces

Then afte confirming the changes with testparm you can restart samba: sudo systemctl restart smbd.service