netibios name len

Christopher R. Hertel crh at
Thu Nov 21 17:01:41 GMT 2002

On Thu, Nov 21, 2002 at 03:17:05PM +0100, Paolo Abeni wrote:
> hi there,
> I had some troubles while configuring a samba printer. The "host"
> component of the netbios resource name was longer than 15 bytes and my
> smbclient (version 2.2.5) truncates the netbois host name at that
> length.

NetBIOS names are 16 bytes maximum, and Microsoft reserves the 16th byte 
for special use.

> Looking at rfc 1002 I have found a 64 byte limit for resource name, but
> apparently there is no strict constraint for the host name, so I thought
> it could be useful to remove this hard-coded limit and admit 64 byte
> long netbios names. is it right???

I'm afraid not.

As I said above, NetBIOS names are 16 bytes maximum and always have been.
They are encoded to a format that is 32-bytes long and then encoded again 
before they are sent on the wire.  Check your Ethereal traces.

The 63-byte limit is for a label in the scope ID.  It is the same limit
that was originally imposed upon DNS labels.  It's 63 bytes because the
value must fit into a 6-bit field.  The two additional bits are used as

See the docs at

Chris -)-----

Samba Team --     -)-----   Christopher R. Hertel
jCIFS Team --   -)-----   ubiqx development, uninq.
ubiqx Team --     -)-----   crh at
OnLineBook --    -)-----   crh at

More information about the samba-technical mailing list