Creating Null Session Shares

1. NSS for RIS clients

When network installing Microsoft RIS OSs (Windows 2000, Windows XP, Windows Server 2003) it is necessary the creation of a "Null Session Share" (NSS). This kind of share got some bad reputation in the past from a security point of view, therefore setting them up on modern OSs it's not just a straight forward single-step action; it involves a bit of effort. This section tries to help Serva users creating their NSSs on different host platforms.

Select your host OS.

Windows 2000

Windows XP

Windows Server 2003

Windows Vista

Windows Server 2008

Windows 7

Windows Server 2012

Windows 8/8.1

Windows 10

 

2. NSS for older clients

The SMB (Server Message Block) Protocol used by Microsoft shares supports dialect negotiation. A dialect is a version of the Protocol that is generally defined in terms of additions and changes relative to a previous version.
RIS clients when requiring the services of the NSS are able to negotiate a dialect called "CIFS" (also known as “NT LAN Manager” or, simply “NT LANMAN”) which is identified by the dialect string "NT LM 0.12". The instructions for creating an NSS included in the previous section, consider all RIS clients are by default able to use the "NT LM 0.12" dialect against any host running Windows 2000 and up.

In the case you need to create an NSS for a client (other than RIS) that mandatorily requires older dialects like “LANMAN1.0”, “LANMAN1.2”, etc, then you might need extra steps in order to enable those old dialects in your host; i.e.
Run the program "Regedit"

  1. Navigate to:
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lanmanserver\parameters\

    Edit the multi-string (REG_MULTI_SZ) value "NullSessionShares" and add the share name on a new line.

  2. Navigate to:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\LSA\

    Edit the 32-bit value (REG_DWORD) value "restrictanonymous" and set it to 0.

NOTE 1: These additional steps are not required if you are just trying to install a RIS OS with Serva.

NOTE 2: Some of the described procedures involve registry editing and other administrative tasks. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs.



Confirmed errors or comments on how to improve the information contained in this document please contact us here.

 

Updated 11/12/2018
Originally published 05/08/2012