docs-xml/Samba3-HOWTO/TOSHARG-TDBFiles.xml

   1 <?xml version="1.0" encoding="iso-8859-1"?>
   2 <!DOCTYPE chapter PUBLIC "-//Samba-Team//DTD DocBook V4.2-Based Variant V1.0//EN" "http://www.samba.org/samba/DTD/samba-doc">
   3 <chapter id="tdb">
   4
   5 <chapterinfo>
   6         &author.jht;
   7
   8         <pubdate>May 28, 2008</pubdate>
   9 </chapterinfo>
  10
  11 <title>Managing TDB Files</title>
  12
  13 <sect1>
  14 <title>Features and Benefits</title>
  15
  16         <para>
  17 <indexterm><primary>tdb</primary></indexterm>
  18 <indexterm><primary>Trivial Database</primary></indexterm>
  19         Samba uses a lightweight database called Trivial Database (tdb) in which it stores persistent and transient data.
  20         Some tdb files can be disposed of before restarting Samba, but others are used to store information that is vital
  21         to Samba configuration and behavior. The following information is provided to help administrators who are seeking
  22         to better manage their Samba installations.
  23         </para>
  24
  25         <para>
  26 <indexterm><primary>tdb</primary></indexterm>
  27 <indexterm><primary>corrupted</primary></indexterm>
  28 <indexterm><primary>backup</primary></indexterm>
  29 <indexterm><primary>restore</primary></indexterm>
  30         Those who package Samba for commercial distribution with operating systems and appliances would do well to take
  31         note that tdb files can get corrupted, and for this reason ought to be backed up regularly.  An appropriate time
  32         is at system shutdown (backup) and startup (restore from backup).
  33         </para>
  34
  35 <para>
  36 <indexterm><primary>NTDB</primary></indexterm>
  37 </para>
  38         As of Samba 4.1, the NTDB format can be used if 'use ntdb' is set.  In this case, tdb files are automatically converted to ntdb files (with the .ntdb extension).  The old .tdb file is turned into a dangling symlink to 'This is now in an NTDB' to prevent it being accidentally used).  The table indicates what databases are currently available as NTDB files.
  39
  40 <table frame="all" id="TOSH-TDB">
  41                 <title>Samba's Trivial Database Files</title>
  42                 <tgroup align="center" cols="2">
  43                 <thead>
  44                 <row><entry>File name</entry><entry>Preserve</entry><entry>NTDB</entry><entry>Description</entry></row>
  45                 </thead>
  46
  47                 <tbody>
  48                         <row><entry>account_policy.tdb</entry><entry>Y</entry><entry>N</entry>
  49                                 <entry><para>NT account policy settings such as pw expiration, etc...</para></entry></row>
  50                         <row><entry>brlock.tdb</entry><entry>N</entry><entry>N</entry>
  51                                 <entry><para>Byte range locks.</para></entry></row>
  52                         <row><entry>browse.dat</entry><entry>N</entry><entry>N</entry>
  53                                 <entry><para>Browse lists - gets rebuilt automatically.</para></entry></row>
  54                         <row><entry>connections.tdb</entry><entry>N</entry><entry>N</entry>
  55                                 <entry><para>Share connections. Used to enforce max connections, etc.</para></entry></row>
  56                         <row><entry>gencache.tdb</entry><entry>N</entry><entry>N</entry>
  57                                 <entry><para>Generic caching database.</para></entry></row>
  58                         <row><entry>group_mapping.tdb</entry><entry>Y</entry><entry>N</entry>
  59                                 <entry><para>Stores group mapping information. Not used when using LDAP backend.</para></entry></row>
  60                         <row><entry>  lang_en.tdb</entry><entry>Y</entry><entry>N</entry>
  61                                 <entry><para>Stores language encoding information.</para></entry></row>
  62                         <row><entry>locking.tdb</entry><entry>N</entry><entry>N</entry>
  63                                 <entry><para>Stores share mode and oplock information.</para></entry></row>
  64                         <row><entry>login_cache.tdb</entry><entry>N</entry><entry>N</entry>
  65                                 <entry><para>Keeps a log of bad pw attempts.</para></entry></row>
  66                         <row><entry>messages.tdb</entry><entry>N</entry><entry>N</entry>
  67                                 <entry><para>Used to keep track of Samba internal messaging.</para></entry></row>
  68                         <row><entry>netsamlogon_cache.tdb</entry><entry>Y</entry><entry>N</entry>
  69                                 <entry><para>
  70                                         Cache of user net_info_3 struct from <emphasis>net_samlogon()</emphasis>
  71                                         requests from domain member machines.
  72                                 </para></entry></row>
  73                         <row><entry>ntdrivers.tdb</entry><entry>Y</entry><entry>N</entry>
  74                                 <entry><para>Stores installed printer driver information.</para></entry></row>
  75                         <row><entry>ntforms.tdb</entry><entry>Y</entry><entry>N</entry>
  76                                 <entry><para>Stores installed printer forms information.</para></entry></row>
  77                         <row><entry>ntprinters.tdb</entry><entry>Y</entry><entry>N</entry>
  78                                 <entry><para>Stores installed printers information.</para></entry></row>
  79                         <row><entry>printing directory</entry><entry>Y</entry><entry>N</entry>
  80                                 <entry><para>Directory containing tdb per print queue of cached lpq output.</para></entry></row>
  81                         <row><entry>registry.tdb</entry><entry>Y</entry><entry>N</entry>
  82                                 <entry><para>Windows registry skeleton (connect via regedit.exe).</para></entry></row>
  83                         <row><entry>sessionid.tdb</entry><entry>N</entry><entry>N</entry>
  84                                 <entry><para>Session information to support <literal>utmp = yes</literal> capabilities.</para></entry></row>
  85                         <row><entry>share_info.tdb</entry><entry>Y</entry><entry>N</entry>
  86                                 <entry><para>Stores share-level ACL configuration settings.
  87                                         Default ACL is <emphasis>Everyone - Full Control</emphasis>.
  88                                 </para></entry></row>
  89                         <row><entry>unexpected.tdb</entry><entry>N</entry><entry>N</entry>
  90                                 <entry><para>
  91                                         Unexpected packet queue needed to support windows clients that respond on a
  92                                         different port that the originating reques.
  93                                 </para></entry></row>
  94                         <row><entry>winbindd_cache.tdb</entry><entry>N</entry><entry>N</entry>
  95                                 <entry><para>Winbind's cache of user lists.</para></entry></row>
  96                         <row><entry>winbindd_idmap.tdb</entry><entry>Y</entry><entry>N</entry>
  97                                 <entry><para>Winbind's local IDMAP database.</para></entry></row>
  98                         <row><entry>wins.dat</entry><entry>N</entry><entry>N</entry>
  99                                 <entry><para>
 100                                 WINS database iused only when <parameter>wins support = yes</parameter>
 101                                 has been set. This gets rebuilt or updated at every restart.
 102                                 </para></entry></row>
 103                         <row><entry>wins.tdb</entry><entry>Y</entry><entry>N</entry>
 104                                 <entry><para>
 105                                 The working permanent storage for all WINS data. This database is used only
 106                                 when <parameter>wins support = yes</parameter> has been set in the &smb.conf; file.
 107                                 Note: This retains all manually configured WINS entries. Manual setting can be done use the net utility.
 108                                 </para></entry></row>
 109                         <row><entry>secrets.tdb</entry><entry>Y</entry><entry>Y</entry>
 110                                 <entry><para>
 111                                 This tdb file stores internal settings such as the machine and the domain SID, secret passwords
 112                                 that are used with LDAP, the machine secret token, etc. This is an essential file that is stored
 113                                 in a secure area. Vendors locate this in various folders. Check <command>smbd -b</command> to
 114                                 find its location on your system.
 115                                 </para></entry></row>
 116                         <row><entry>schannel_store.tdb</entry><entry>Y</entry><entry>Y</entry>
 117                                 <entry><para>
 118                                 This stores secure channel access token information used with SMB signing.
 119                                 </para></entry></row>
 120                         <row><entry>passdb.tdb</entry><entry>Y</entry><entry>N</entry>
 121                                 <entry><para>
 122                                 This stores the Samba SAM account information when using a tdbsam password backend.
 123                                 </para></entry></row>
 124                 </tbody>
 125         </tgroup>
 126         </table>
 127
 128 </sect1>
 129
 130 <sect1>
 131 <title>Managing TDB Files</title>
 132
 133         <para>
 134         The <command>tdbbackup</command> utility is a tool that may be used to backup samba tdb files.
 135         This tool may also be used to verify the integrity of the tdb files prior to Samba startup or
 136         during normal operation. If it finds file damage it will search for a prior backup the backup
 137         file from which the damaged tdb file will be restored. The <command>tdbbackup</command>
 138         utility can safely be run at any time. It was designed so that it can be used at any time to
 139         validate the integrity of tdb files, even during Samba operation.
 140         </para>
 141
 142         <para>
 143         It is recommended to backup all tdb files as part of the Samba start-up scripts on a Samba
 144         server. The following command syntax can be used:
 145         </para>
 146 <screen>
 147 myserver# > cd /var/lib/samba
 148 myserver@ > tdbbackup *.tdb
 149 </screen>
 150         <para>
 151         The default extension is <filename>.bak</filename>. Any alternate extension can be specified
 152         by executing <literal>tdbbackup -s 'new_extension' *.tdb</literal> as part of your startup script.
 153         </para>
 154
 155 </sect1>
 156
 157 </chapter>