machine names same as usernames -> problems... -- here's a "real world" NetBIOS clusterfsck ...

Bryan J. Smith b.j.smith at
Thu Feb 6 20:54:30 GMT 2003

Quoting Andrew Bartlett <abartlet at>:
> Why can't it work?  I've seen this discussed a number of times, but
> never really been told why it doesn't work.  That $ is there for
> exactly that reason you know - to make them different.  

Er, not exactly.  If I remember correctly, the "$" in the passwd file just a
Samba-specific nomenclature, correct?  Plus CIFS has all sorts of "trailing
characters" after NetBIOS names that are _not_ part of the unique NetBIOS name

Understand CIFS itself _requires_ NetBIOS names _must_ be _unique_, otherwise a
service or resource may be attempting to connect to the address of a NetBIOS
"user" (impossible) instead of the address of a NetBIOS "system".

FIRST HAND EXPERIENCE (as I documented in "Samba Unleashed") ...

I've seen this _first_hand_ with a Casiopeia PDA, and a user go nuts for over a
day with Casio's tech support.  This was right after the first CE devices had
some out.  He was trying to get it to sync with Outlook running on NT 4.0
Workstation.  I came over, saw that it used RAS, and instantly "took a shot" at
the problem being related to using the same NetBIOS name for both the username
and systemname.

Sure enough, it was.  I called Casiopeia and let them know.  A few weeks later,
I was called back and _thanked_ for identifying that, because they had a _lot_
of calls that they were able to solve from that point on.  One technician even
told me that problem had been escalated to Microsoft themselves, who said "doh,
we should have thought of checking that" after hearing of my resolution.  Again,
this is right after the first CE devices, like the Casiopeias, had come out and
just started to become widespread.

[ I also actually hadn't been at that job very long either, and it help me
"drive my point home" that users should _not_ be renaming their systems to their
username. ;-> ]

> I think it's not good practice to have machine names and usernames
> be the same but i also don't think samba should fail cryptically in
> that situation...

As with most things CIFS/SMB, it's _not_ Samba but the Windows _clients_
themselves.  Windows _clients_ often make assumptions, don't differentiate
between resources, etc... and are _never_ coded to resolve such things.

Bryan J. Smith             |  Peace is a fruitless endeavor           |  When a defeated aggressor
Engineer, IT Professional  |  Has not, will not nor will ever
Proud American Forever     |  Adhere to terms of its surrender

More information about the samba-technical mailing list