[Samba] Problem with Domain SID

simo idra at samba.org
Thu Aug 17 12:37:05 GMT 2006

On Thu, 2006-08-17 at 14:20 +0200, Marcus Haarmann wrote:
> Hi Andre,
> The machine was off-network for two days only. 
> The problem is not machine based, but server based. The server SID has
> definetely changed since the user was created (and the machine joined the
> domain).
> I found out in the meantime that the users SID contains the domain SID (this
> can be retrieved in registry under HKEY_USERS, strip the last two bytes and
> you have the domain SID), where it was created with. Unfortunately, there is
> no simple way setting it in samba (like net setsid ... for domain SID, only
> the PDC sid can be set). I have done this using a hex editor, patching
> secrets.tdb (SID of PDC and Domain, these are identical, at our site). 
> So, the problem is half-way solved.

The 'net' command provides the setlocalsid and setdomainsid functions
for setting the SIDs, there is no need to use hex editors. (setdomainsid
may be available on 3.0.23 only)

> The server now has the old sid again, which was presumably changed more than
> half a year ago (modification time of secrets.tdb was December 2005). I

I remember there is some kernel bug on some versions of the kernel, that
do not update the mtime when the file is mmapped, it may have changed
just recently (and is probably so, as you would have had problems much
eralier otherwise).

> cannot say why the entrustment from this special machine has been broken,
> but now I am able to log on to the domain as any user on all machines again.
> (which have joined the domain before the SID change).
> The only thing is that we added one machine after the modification of the
> Domain-SID, we have to see how this machine behaves. I am now trying to
> reactivate the old profile of the user who was not able to log in.
> For the machine which joined the domain after the SID change, we might have
> to rejoin the machine to the domain, unless anybody can tell me how this
> trustment can be reassigned without a profile change ...

you can use the 'profiles' tool to change all the SIDs in the user
profile file (NTUSER.DAT)


Simo Sorce
Samba Team GPL Compliance Officer
email: idra at samba.org

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