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>currupted</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 <table frame="all" id="TOSH-TDB">
  36                 <title>Samba's Trivial Database Files</title>
  37                 <tgroup align="center" cols="2">
  38                 <thead>
  39                 <row><entry>File name</entry><entry>Preserve</entry><entry>Description</entry></row>
  40                 </thead>
  41
  42                 <tbody>
  43                         <row><entry>account_policy.tdb</entry><entry>Y</entry>
  44                                 <entry><para>NT account policy settings such as pw expiration, etc...</para></entry></row>
  45                         <row><entry>brlock.tdb</entry><entry>N</entry>
  46                                 <entry><para>Byte range locks.</para></entry></row>
  47                         <row><entry>browse.dat</entry><entry>N</entry>
  48                                 <entry><para>Browse lists - gets rebuilt automatically.</para></entry></row>
  49                         <row><entry>connections.tdb</entry><entry>N</entry>
  50                                 <entry><para>Share connections. Used to enforce max connections, etc.</para></entry></row>
  51                         <row><entry>gencache.tdb</entry><entry>N</entry>
  52                                 <entry><para>Generic caching database.</para></entry></row>
  53                         <row><entry>group_mapping.tdb</entry><entry>Y</entry>
  54                                 <entry><para>Stores group mapping information. Not used when using LDAP backend.</para></entry></row>
  55                         <row><entry>  lang_en.tdb</entry><entry>Y</entry>
  56                                 <entry><para>Stores language encoding information.</para></entry></row>
  57                         <row><entry>locking.tdb</entry><entry>N</entry>
  58                                 <entry><para>Stores share mode and oplock information.</para></entry></row>
  59                         <row><entry>login_cache.tdb</entry><entry>N</entry>
  60                                 <entry><para>Keeps a log of bad pw attempts.</para></entry></row>
  61                         <row><entry>messages.tdb</entry><entry>N</entry>
  62                                 <entry><para>Used to keep track of Samba internal messaging.</para></entry></row>
  63                         <row><entry>netsamlogon_cache.tdb</entry><entry>Y</entry>
  64                                 <entry><para>
  65                                         Cache of user net_info_3 struct from <emphasis>net_samlogon()</emphasis>
  66                                         requests from domain member machines.
  67                                 </para></entry></row>
  68                         <row><entry>ntdrivers.tdb</entry><entry>Y</entry>
  69                                 <entry><para>Stores installed printer driver information.</para></entry></row>
  70                         <row><entry>ntforms.tdb</entry><entry>Y</entry>
  71                                 <entry><para>Stores installed printer forms information.</para></entry></row>
  72                         <row><entry>ntprinters.tdb</entry><entry>Y</entry>
  73                                 <entry><para>Stores installed printers information.</para></entry></row>
  74                         <row><entry>printing directory</entry><entry>Y</entry>
  75                                 <entry><para>Directory containing tdb per print queue of cached lpq output.</para></entry></row>
  76                         <row><entry>registry.tdb</entry><entry>Y</entry>
  77                                 <entry><para>Windows registry skeleton (connect via regedit.exe).</para></entry></row>
  78                         <row><entry>sessionid.tdb</entry><entry>N</entry>
  79                                 <entry><para>Session information to support <literal>utmp = yes</literal> capabilities.</para></entry></row>
  80                         <row><entry>share_info.tdb</entry><entry>Y</entry>
  81                                 <entry><para>Stores share-level ACL configuration settings.
  82                                         Default ACL is <emphasis>Everyone - Full Control</emphasis>.
  83                                 </para></entry></row>
  84                         <row><entry>unexpected.tdb</entry><entry>N</entry>
  85                                 <entry><para>
  86                                         Unexpected packet queue needed to support windows clients that respond on a
  87                                         different port that the originating reques.
  88                                 </para></entry></row>
  89                         <row><entry>winbindd_cache.tdb</entry><entry>N</entry>
  90                                 <entry><para>Winbind's cache of user lists.</para></entry></row>
  91                         <row><entry>winbindd_idmap.tdb</entry><entry>Y</entry>
  92                                 <entry><para>Winbind's local IDMAP database.</para></entry></row>
  93                         <row><entry>wins.dat</entry><entry>N</entry>
  94                                 <entry><para>
  95                                 WINS database iused only when <parameter>wins support = yes</parameter>
  96                                 has been set. This gets rebuilt or updated at every restart.
  97                                 </para></entry></row>
  98                         <row><entry>wins.tdb</entry><entry>Y</entry>
  99                                 <entry><para>
 100                                 The working permanent storage for all WINS data. This database is used only
 101                                 when <parameter>wins support = yes</parameter> has been set in the &smb.conf; file.
 102                                 Note: This retains all manually configured WINS entries. Manual setting can be done use the net utility.
 103                                 </para></entry></row>
 104                         <row><entry>secrets.tdb</entry><entry>Y</entry>
 105                                 <entry><para>
 106                                 This tdb file stores internal settings such as the machine and the domain SID, secret passwords
 107                                 that are used with LDAP, the machine secret token, etc. This is an essential file that is stored
 108                                 in a secure area. Vendors locate this in various folders. Check <command>smbd -b</command> to
 109                                 find its location on your system.
 110                                 </para></entry></row>
 111                         <row><entry>schannel_store.tdb</entry><entry>Y</entry>
 112                                 <entry><para>
 113                                 This stores secure channel access token information used with SMB signing.
 114                                 </para></entry></row>
 115                         <row><entry>passdb.tdb</entry><entry>Y</entry>
 116                                 <entry><para>
 117                                 This stores the Samba SAM account information when using a tdbsam password backend.
 118                                 </para></entry></row>
 119                 </tbody>
 120         </tgroup>
 121         </table>
 122
 123 </sect1>
 124
 125 <sect1>
 126 <title>Managing TDB Files</title>
 127
 128         <para>
 129         The <command>tdbbackup</command> utility is a tool that may be used to backup samba tdb files.
 130         This tool may also be used to verify the integrity of the tdb files prior to Samba startup or
 131         during normal operation. If it finds file damage it will search for a prior backup the backup
 132         file from which the damaged tdb file will be restored. The <command>tdbbackup</command>
 133         utility can safely be run at any time. It was designed so that it can be used at any time to
 134         validate the integrity of tdb files, even during Samba operation.
 135         </para>
 136
 137         <para>
 138         It is recommended to backup all tdb files as part of the Samba start-up scripts on a Samba
 139         server. The following command syntax can be used:
 140         </para>
 141 <screen>
 142 myserver# > cd /var/lib/samba
 143 myserver@ > tdbbackup *.tdb
 144 </screen>
 145         <para>
 146         The default extension is <filename>.bak</filename>. Any alternate extension can be specified
 147         by executing <literal>tdbbackup -s 'new_extension' *.tdb</literal> as part of your startup script.
 148         </para>
 149
 150 </sect1>
 151
 152 </chapter>