Samba service


Samba provides Windows networking services using a Unix machine.

The resources available on a Windows Network is called the browse list. The browse list is maintained on a computer called the Master Browser. For a Windows network spanning multiple subnets, a domain master browser collects the browse list for the entire domain. The fys domain master brower is intra. You can view the current browse list from a unix machine using, the smbclient command:

smbclient -L intra

This could look like this:

Domain=[INTRA] OS=[Unix] Server=[Samba 3.0.9-1.3E.5]

       Sharename       Type      Comment
       ---------       ----      -------
       camp            Disk      CAMP group shared directory
       mossbauer       Disk      Mossbauer group shared directory
       mossbauerWWW    Disk      Mossbauer group WWW directory
       mossstud        Disk      Mossbauer group student directory
       WWW             Disk      World Wide Web data for
       wwwstm          Disk      STM WWW-files (restricted access)
       cinfWWW         Disk      CINF WWW-server files (restricted access)
       NanoteketWWW    Disk      Nanoteket WWW-server files (restricted access)
       cinfDB          Disk      CINF Database files (access only for CINF)
       IPC$            IPC       IPC Service (INTRA FYS Samba Server)
       ADMIN$          IPC       IPC Service (INTRA FYS Samba Server)
       camp4200        Printer   Created by redhat-config-printer 0.6.x
       lhansen         Disk      Home Directories
Domain=[INTRA] OS=[Unix] Server=[Samba 3.0.9-1.3E.5]

       Server               Comment
       ---------            -------

       Workgroup            Master
       ---------            -------
       AABOULEVARD          RUBECH
       FYS                  INTRA
       MSHOME               MATRIXII

NetBIOS resolution of names across subnet is done, not using DNS, but Windows Internet Name Service or WINS. WINS provides a dynamically updated central database, which can be used to resolve hostnames into IP adresses.

The smb.conf file

This section describes the changes from the default smb.conf at fys:


workgroup = FYS

server string = INTRA FYS Samba Server  # Replace "INTRA" by actual server name

hosts allow  = 130.225.86. 130.225.87. 127.l

max log size = 1000

password level = 2
username level = 2

local master = yes
os level = 60

domain master = yes

preferred master = yes

wins support = yes

wins proxy = yes
dns proxy = yes

# local setup
display charset = UTF8
utmp = yes

create mask = 0644
directory mask = 0755

Other shares defined at fys:

  • homes

  • mossbauer

In these setting the netbios name is not set explicitly. The netbios name will in this case get the first part of DNS name.

The netbios name can be changed using:

netbios name = intra

SAMBA password database

We use Samba’s default database for storing passwords, as configured in smb.conf:

security = user
passdb backend = tdbsam

Use this command to list the contents of the TDBSAM password database:

/usr/bin/pdbedit -L
/usr/bin/pdbedit -L -w -u <USERNAME>

Use the pdbedit -i command to insert a new user into the database. To delete an existing user from the database:

pdbedit -x -u <USERNAME>

Location of SAMBA password database

The TDBSAM password database file is passdb.tdb. With Samba version 3.3 and above (used by RHEL6/CentOS6), the password database is located in:


The Samba-3 docs show a general method for determining the TDB Database File Information where the file location is given by PRIVATE_DIR:

root# smbd -b | grep PRIVATE_DIR
PRIVATE_DIR: /etc/samba/private

WINS server

The FYS Workgroup spans across mutiple TCP/IP subnets. NETBIOS name resolution in this situation relies on a WINS (Windows Internet Name Service) server to resolve NETBIOS names. In our case the Samba server is set up to be the WINS server. This is done in the smb.conf file (wins support = yes).

The IP adress of the WINS server must be supplied to dhcpd via the netbios-name-servers:

option netbios-name-servers;