docs/docbook/projdoc/DOMAIN_MEMBER.sgml

   1 <chapter>
   2
   3 <chapterinfo>
   4         <author>
   5                 <firstname>Jeremy</firstname><surname>Allison</surname>
   6                 <affiliation>
   7                         <orgname>Samba Team</orgname>
   8                         <address>
   9                                 <email>samba@samba.org</email>
  10                         </address>
  11                 </affiliation>
  12         </author>
  13         <author>
  14                 <firstname>Jerry</firstname><surname>Carter</surname>
  15                 <affiliation>
  16                         <orgname>Samba Team</orgname>
  17                         <address>
  18                                 <email>jerry@samba.org</email>
  19                         </address>
  20                 </affiliation>
  21         </author>
  22
  23
  24         <pubdate>16 Apr 2001</pubdate>
  25 </chapterinfo>
  26
  27
  28 <title>security = domain in Samba 2.x</title>
  29
  30 <sect1>
  31
  32         <title>Joining an NT Domain with Samba 2.2</title>
  33
  34         <para>In order for a Samba-2 server to join an NT domain,
  35         you must first add the NetBIOS name of the Samba server to the
  36         NT domain on the PDC using Server Manager for Domains.  This creates
  37         the machine account in the domain (PDC) SAM. Note that you should
  38         add the Samba server as a "Windows NT Workstation or Server",
  39         <emphasis>NOT</emphasis> as a Primary or backup domain controller.</para>
  40
  41         <para>Assume you have a Samba-2 server with a NetBIOS name of
  42         <constant>SERV1</constant> and are joining an NT domain called
  43         <constant>DOM</constant>, which has a PDC with a NetBIOS name
  44         of <constant>DOMPDC</constant> and two backup domain controllers
  45         with NetBIOS names <constant>DOMBDC1</constant> and <constant>DOMBDC2
  46         </constant>.</para>
  47
  48         <para>In order to join the domain, first stop all Samba daemons
  49         and run the command:</para>
  50
  51         <para><prompt>root# </prompt><userinput>smbpasswd -j DOM -r DOMPDC
  52         </userinput></para>
  53
  54         <para>as we are joining the domain DOM and the PDC for that domain
  55         (the only machine that has write access to the domain SAM database)
  56         is DOMPDC. If this is successful you will see the message:</para>
  57
  58         <para><computeroutput>smbpasswd: Joined domain DOM.</computeroutput>
  59         </para>
  60
  61         <para>in your terminal window. See the <ulink url="smbpasswd.8.html">
  62         smbpasswd(8)</ulink> man page for more details.</para>
  63
  64         <para>There is existing development code to join a domain
  65         without having to create the machine trust account on the PDC
  66         beforehand.  This code will hopefully be available soon
  67         in release branches as well.</para>
  68
  69         <para>This command goes through the machine account password
  70         change protocol, then writes the new (random) machine account
  71         password for this Samba server into a file in the same directory
  72         in which an smbpasswd file would be stored - normally :</para>
  73
  74         <para><filename>/usr/local/samba/private</filename></para>
  75
  76         <para>In Samba 2.0.x, the filename looks like this:</para>
  77
  78         <para><filename><replaceable>&lt;NT DOMAIN NAME&gt;</replaceable>.<replaceable>&lt;Samba
  79         Server Name&gt;</replaceable>.mac</filename></para>
  80
  81         <para>The <filename>.mac</filename> suffix stands for machine account
  82         password file. So in our example above, the file would be called:</para>
  83
  84         <para><filename>DOM.SERV1.mac</filename></para>
  85
  86         <para>In Samba 2.2, this file has been replaced with a TDB
  87         (Trivial Database) file named <filename>secrets.tdb</filename>.
  88         </para>
  89
  90
  91         <para>This file is created and owned by root and is not
  92         readable by any other user. It is the key to the domain-level
  93         security for your system, and should be treated as carefully
  94         as a shadow password file.</para>
  95
  96         <para>Now, before restarting the Samba daemons you must
  97         edit your <ulink url="smb.conf.5.html"><filename>smb.conf(5)</filename>
  98         </ulink> file to tell Samba it should now use domain security.</para>
  99
 100         <para>Change (or add) your <ulink url="smb.conf.5.html#SECURITY">
 101         <parameter>security =</parameter></ulink> line in the [global] section
 102         of your smb.conf to read:</para>
 103
 104         <para><command>security = domain</command></para>
 105
 106         <para>Next change the <ulink url="smb.conf.5.html#WORKGROUP"><parameter>
 107         workgroup =</parameter></ulink> line in the [global] section to read: </para>
 108
 109         <para><command>workgroup = DOM</command></para>
 110
 111         <para>as this is the name of the domain we are joining. </para>
 112
 113         <para>You must also have the parameter <ulink url="smb.conf.5.html#ENCRYPTPASSWORDS">
 114         <parameter>encrypt passwords</parameter></ulink> set to <constant>yes
 115         </constant> in order for your users to authenticate to the NT PDC.</para>
 116
 117         <para>Finally, add (or modify) a <ulink url="smb.conf.5.html#PASSWORDSERVER">
 118         <parameter>password server =</parameter></ulink> line in the [global]
 119         section to read: </para>
 120
 121         <para><command>password server = DOMPDC DOMBDC1 DOMBDC2</command></para>
 122
 123         <para>These are the primary and backup domain controllers Samba
 124         will attempt to contact in order to authenticate users. Samba will
 125         try to contact each of these servers in order, so you may want to
 126         rearrange this list in order to spread out the authentication load
 127         among domain controllers.</para>
 128
 129         <para>Alternatively, if you want smbd to automatically determine
 130         the list of Domain controllers to use for authentication, you may
 131         set this line to be :</para>
 132
 133         <para><command>password server = *</command></para>
 134
 135         <para>This method, which was introduced in Samba 2.0.6,
 136         allows Samba to use exactly the same mechanism that NT does. This
 137         method either broadcasts or uses a WINS database in order to
 138         find domain controllers to authenticate against.</para>
 139
 140         <para>Finally, restart your Samba daemons and get ready for
 141         clients to begin using domain security!</para>
 142 </sect1>
 143
 144 <sect1>
 145 <title>Samba and Windows 2000 Domains</title>
 146
 147 <para>
 148 Many people have asked regarding the state of Samba's ability to participate in
 149 a Windows 2000 Domain.  Samba 2.2 is able to act as a member server of a Windows
 150 2000 domain operating in mixed or native mode.
 151 </para>
 152
 153 <para>
 154 There is much confusion between the circumstances that require a "mixed" mode
 155 Win2k DC and a when this host can be switched to "native" mode.  A "mixed" mode
 156 Win2k domain controller is only needed if Windows NT BDCs must exist in the same
 157 domain.  By default, a Win2k DC in "native" mode will still support
 158 NetBIOS and NTLMv1 for authentication of legacy clients such as Windows 9x and
 159 NT 4.0.  Samba has the same requirements as a Windows NT 4.0 member server.
 160 </para>
 161
 162 <para>
 163 The steps for adding a Samba 2.2 host to a Win2k domain are the same as those
 164 for adding a Samba server to a Windows NT 4.0 domain. The only exception is that
 165 the "Server Manager" from NT 4 has been replaced by the "Active Directory Users and
 166 Computers" MMC (Microsoft Management Console) plugin.
 167 </para>
 168
 169 </sect1>
 170
 171
 172 <sect1>
 173         <title>Why is this better than security = server?</title>
 174
 175         <para>Currently, domain security in Samba doesn't free you from
 176         having to create local Unix users to represent the users attaching
 177         to your server. This means that if domain user <constant>DOM\fred
 178         </constant> attaches to your domain security Samba server, there needs
 179         to be a local Unix user fred to represent that user in the Unix
 180         filesystem. This is very similar to the older Samba security mode
 181         <ulink url="smb.conf.5.html#SECURITYEQUALSSERVER">security = server</ulink>,
 182         where Samba would pass through the authentication request to a Windows
 183         NT server in the same way as a Windows 95 or Windows 98 server would.
 184         </para>
 185
 186         <para>Please refer to the <ulink url="winbind.html">Winbind
 187         paper</ulink> for information on a system to automatically
 188         assign UNIX uids and gids to Windows NT Domain users and groups.
 189         This code is available in development branches only at the moment,
 190         but will be moved to release branches soon.</para>
 191
 192         <para>The advantage to domain-level security is that the
 193         authentication in domain-level security is passed down the authenticated
 194         RPC channel in exactly the same way that an NT server would do it. This
 195         means Samba servers now participate in domain trust relationships in
 196         exactly the same way NT servers do (i.e., you can add Samba servers into
 197         a resource domain and have the authentication passed on from a resource
 198         domain PDC to an account domain PDC.</para>
 199
 200         <para>In addition, with <command>security = server</command> every Samba
 201         daemon on a server has to keep a connection open to the
 202         authenticating server for as long as that daemon lasts. This can drain
 203         the connection resources on a Microsoft NT server and cause it to run
 204         out of available connections. With <command>security = domain</command>,
 205         however, the Samba daemons connect to the PDC/BDC only for as long
 206         as is necessary to authenticate the user, and then drop the connection,
 207         thus conserving PDC connection resources.</para>
 208
 209         <para>And finally, acting in the same manner as an NT server
 210         authenticating to a PDC means that as part of the authentication
 211         reply, the Samba server gets the user identification information such
 212         as the user SID, the list of NT groups the user belongs to, etc. All
 213         this information will allow Samba to be extended in the future into
 214         a mode the developers currently call appliance mode. In this mode,
 215         no local Unix users will be necessary, and Samba will generate Unix
 216         uids and gids from the information passed back from the PDC when a
 217         user is authenticated, making a Samba server truly plug and play
 218         in an NT domain environment. Watch for this code soon.</para>
 219
 220         <para><emphasis>NOTE:</emphasis> Much of the text of this document
 221         was first published in the Web magazine <ulink url="http://www.linuxworld.com">
 222         LinuxWorld</ulink> as the article <ulink
 223         url="http://www.linuxworld.com/linuxworld/lw-1998-10/lw-10-samba.html">Doing
 224         the NIS/NT Samba</ulink>.</para>
 225
 226 </sect1>
 227
 228 </chapter>