Why does smbpasswd not work for some users?

[Craig White]

On Fri, 2008-08-29 at 15:25 +0100, Bob Latham wrote:
> In article <1220018091.2949.4.camel at lin-workstation.azapple.com>,
>    Craig White <craigwhite at azapple.com> wrote:
> > On Fri, 2008-08-29 at 14:40 +0100, Bob Latham wrote:
> > > In article <1219990339.2949.1.camel at lin-workstation.azapple.com>,
> > >    Craig White <craigwhite at azapple.com> wrote:
> > > > On Fri, 2008-08-29 at 10:04 +0100, Bob Latham wrote:
> > > > > Hi Everyone,
> > > > > 
> > > > > Using Fedora8.
> > > > > 
> > > > > I find some users I create have no problem having their smb
> > > > > passwords changed using smbpasswd. Others simply don't work and I
> > > > > get the error message "Failed to modify password entry for user
> > > > > <whatever>".
> > > > > 
> > > > > What are the possible causes for this, and could you point me at a
> > > > > method of fixing it please?
> > > > > 
> > > > > I remember from a fiddle I had with Linux some years ago that I
> > > > > used to have to copy the OS user passwords to SMB passwords using
> > > > > a method like this...
> > > > > 
> > > > > cat /etc/passwd | mksmbpasswd.sh > /etc/samba/smbpasswd
> > > > > 
> > > > > Is this procedure still required?
> > > 
> > > > ---- No way...and I don't recall when that ever would have worked.
> > > 
> > > > users changing their password from command line smbpasswd, I've
> > > > never seen that fail. It makes no sense that it would fail.
> > > 
> > > Hi Craig,
> > > 
> > > Thanks for the help.
> > > 
> > > So I should never need to do this?
> > > 
> > > Okay, so how does Samba authenticate users (no other server) is it
> > > with the smbpasswd file? If so how does it get its info?
> > > 
> > > In stupidity and desperation I've managed to break my smbpasswd file.
> > > Now the command smbpasswd -a <name> doesn't function at all. Is there
> > > anyway to repair it? Or get a default copy?
> 
> > ---- not that I am aware of...backup is the method used to protect
> > yourself ----
> 
> Bugger!
>  
> > > The amazing thing is, the samba shares still work after a reboot with
> > > no smbpasswd file. I'm so confused, I think i've got my head around
> > > how it works and then something comes along and proves I had it wrong
> > > again.
> > > 
> > > I only want to set up samba shares. <sob>
> > ---- I'm not sure that Fedora 9 uses an smbpasswd passdb by default.
> 
> I think I'm using Fedora 8. Well, making a dog's breakfast of more like.
> 
> > What is output (as root) of command... testparm -s |grep passdb
> 
> [root at DarkStar ~]# testparm -s |grep passdb
> Load smb config files from /etc/samba/smb.conf
> Processing section "[homes]"
> Processing section "[printers]"
> Processing section "[Staffshare]"
> Processing section "[Studentshare]"
> Processing section "[testshare]"
> Processing section "[itgroup1]"
> Processing section "[manage]"
> Processing section "[sg1]"
> Processing section "[sg2]"
> Loaded services file OK.
> Server role: ROLE_STANDALONE
>         passdb backend = tdbsam
----
that last line, 'passdb backend = tdbsam' means that you aren't using
smbpasswd for your data store for users which is a good thing since
tdbsam is more substantial than a flat file. Users / passwords are
stored in /var/lib/samba/private/passdb.tdb|secrets.tdb

You might want to up the debugging level to find out if/why it's failing
then try that.

Craig