release/src/router/samba3/docs/htmldocs/Samba3-HOWTO/msdfs.html

   1 <html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Chapter 20. Hosting a Microsoft Distributed File System Tree</title><link rel="stylesheet" href="samba.css" type="text/css"><meta name="generator" content="DocBook XSL Stylesheets V1.70.1"><link rel="start" href="index.html" title="The Official Samba-3 HOWTO and Reference Guide"><link rel="up" href="optional.html" title="Part III. Advanced Configuration"><link rel="prev" href="InterdomainTrusts.html" title="Chapter 19. Interdomain Trust Relationships"><link rel="next" href="classicalprinting.html" title="Chapter 21. Classical Printing Support"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 20. Hosting a Microsoft Distributed File System Tree</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="InterdomainTrusts.html">Prev</a> </td><th width="60%" align="center">Part III. Advanced Configuration</th><td width="20%" align="right"> <a accesskey="n" href="classicalprinting.html">Next</a></td></tr></table><hr></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="msdfs"></a>Chapter 20. Hosting a Microsoft Distributed File System Tree</h2></div><div><div class="author"><h3 class="author"><span class="firstname">Shirish</span> <span class="surname">Kalele</span></h3><div class="affiliation"><span class="orgname">Samba Team &amp; Veritas Software<br></span><div class="address"><p><br>
   2                                 <code class="email">&lt;<a href="mailto:samba@samba.org">samba@samba.org</a>&gt;</code><br>
   3                         </p></div></div></div></div><div><div class="author"><h3 class="author"><span class="firstname">John</span> <span class="othername">H.</span> <span class="surname">Terpstra</span></h3><div class="affiliation"><span class="orgname">Samba Team<br></span><div class="address"><p><code class="email">&lt;<a href="mailto:jht@samba.org">jht@samba.org</a>&gt;</code></p></div></div></div></div><div><p class="pubdate">12 Jul 2000</p></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="sect1"><a href="msdfs.html#id2624987">Features and Benefits</a></span></dt><dt><span class="sect1"><a href="msdfs.html#id2625393">Common Errors</a></span></dt><dd><dl><dt><span class="sect2"><a href="msdfs.html#id2625426">MSDFS UNIX Path Is Case-Critical</a></span></dt></dl></dd></dl></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2624987"></a>Features and Benefits</h2></div></div></div><p>
   4 <a class="indexterm" name="id2624995"></a>
   5 <a class="indexterm" name="id2625004"></a>
   6 <a class="indexterm" name="id2625011"></a>
   7 <a class="indexterm" name="id2625018"></a>
   8 <a class="indexterm" name="id2625025"></a>
   9         The distributed file system (DFS) provides a means of separating the logical
  10         view of files and directories that users see from the actual physical locations
  11         of these resources on the network. It allows for higher availability, smoother
  12         storage expansion, load balancing, and so on.
  13         </p><p>
  14 <a class="indexterm" name="id2625040"></a>
  15 <a class="indexterm" name="id2625047"></a>
  16 <a class="indexterm" name="id2625054"></a>
  17         For information about DFS, refer to the <a href="http://www.microsoft.com/NTServer/nts/downloads/winfeatures/NTSDistrFile/AdminGuide.asp" target="_top">Microsoft
  18         documentation</a>.  This document explains how to host a DFS tree on a UNIX machine (for DFS-aware clients
  19         to browse) using Samba.
  20         </p><p>
  21 <a class="indexterm" name="id2625074"></a>
  22 <a class="indexterm" name="id2625081"></a>
  23 <a class="indexterm" name="id2625088"></a>
  24 <a class="indexterm" name="id2625094"></a>
  25         A Samba server can be made a DFS server by setting the global Boolean <a class="indexterm" name="id2625103"></a>host msdfs
  26         parameter in the <code class="filename">smb.conf</code> file. You designate a share as a DFS root using the share-level Boolean
  27         <a class="indexterm" name="id2625117"></a>msdfs root parameter. A DFS root directory on Samba hosts DFS links in the form of
  28         symbolic links that point to other servers. For example, a symbolic link
  29         <code class="filename">junction-&gt;msdfs:storage1\share1</code> in the share directory acts as the DFS junction. When
  30         DFS-aware clients attempt to access the junction link, they are redirected to the storage location (in this
  31         case, <em class="parameter"><code>\\storage1\share1</code></em>).
  32         </p><p>
  33 <a class="indexterm" name="id2625146"></a>
  34 <a class="indexterm" name="id2625153"></a>
  35 <a class="indexterm" name="id2625160"></a>
  36 <a class="indexterm" name="id2625166"></a>
  37         DFS trees on Samba work with all DFS-aware clients ranging from Windows 95 to 200x.
  38         <a href="msdfs.html#dfscfg" title="Example 20.1. smb.conf with DFS Configured">The following sample configuration</a> shows how to setup a DFS tree on a Samba server.
  39         In the <code class="filename">/export/dfsroot</code> directory, you set up your DFS links to
  40         other servers on the network.
  41 </p><pre class="screen">
  42 <code class="prompt">root# </code><strong class="userinput"><code>cd /export/dfsroot</code></strong>
  43 <code class="prompt">root# </code><strong class="userinput"><code>chown root /export/dfsroot</code></strong>
  44 <code class="prompt">root# </code><strong class="userinput"><code>chmod 755 /export/dfsroot</code></strong>
  45 <code class="prompt">root# </code><strong class="userinput"><code>ln -s msdfs:storageA\\shareA linka</code></strong>
  46 <code class="prompt">root# </code><strong class="userinput"><code>ln -s msdfs:serverB\\share,serverC\\share linkb</code></strong>
  47 </pre><p>
  48 </p><div class="example"><a name="dfscfg"></a><p class="title"><b>Example 20.1. smb.conf with DFS Configured</b></p><div class="example-contents"><table class="simplelist" border="0" summary="Simple list"><tr><td> </td></tr><tr><td><em class="parameter"><code>[global]</code></em></td></tr><tr><td><a class="indexterm" name="id2625275"></a><em class="parameter"><code>netbios name = GANDALF</code></em></td></tr><tr><td><a class="indexterm" name="id2625288"></a><em class="parameter"><code>host msdfs   = yes</code></em></td></tr><tr><td> </td></tr><tr><td><em class="parameter"><code>[dfs]</code></em></td></tr><tr><td><a class="indexterm" name="id2625310"></a><em class="parameter"><code>path = /export/dfsroot</code></em></td></tr><tr><td><a class="indexterm" name="id2625323"></a><em class="parameter"><code>msdfs root = yes</code></em></td></tr></table></div></div><br class="example-break"><p>
  49 <a class="indexterm" name="id2625339"></a>
  50 <a class="indexterm" name="id2625346"></a>
  51 <a class="indexterm" name="id2625352"></a>
  52         You should set up the permissions and ownership of the directory acting as the DFS root so that only
  53         designated users can create, delete, or modify the msdfs links. Also note that symlink names should be all
  54         lowercase. This limitation exists to have Samba avoid trying all the case combinations to get at the link
  55         name. Finally, set up the symbolic links to point to the network shares you want and start Samba.
  56         </p><p>
  57 <a class="indexterm" name="id2625370"></a>
  58 <a class="indexterm" name="id2625376"></a>
  59         Users on DFS-aware clients can now browse the DFS tree on the Samba server at
  60         <code class="constant">\\samba\dfs</code>. Accessing links linka or linkb (which appear as directories to the client)
  61         takes users directly to the appropriate shares on the network.
  62         </p></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2625393"></a>Common Errors</h2></div></div></div><div class="itemizedlist"><ul type="disc"><li><p>Windows clients need to be rebooted
  63                 if a previously mounted non-DFS share is made a DFS
  64                 root, or vice versa. A better way is to introduce a
  65                 new share and make it the DFS root.</p></li><li><p>Currently, there's a restriction that msdfs
  66                 symlink names should all be lowercase.</p></li><li><p>For security purposes, the directory
  67                 acting as the root of the DFS tree should have ownership
  68                 and permissions set so only designated users can
  69                 modify the symbolic links in the directory.</p></li></ul></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2625426"></a>MSDFS UNIX Path Is Case-Critical</h3></div></div></div><p>
  70                 A network administrator sent advice to the Samba mailing list
  71                 after long sessions trying to determine why DFS was not working.
  72                 His advice is worth noting.
  73                 </p><p>&#8220;<span class="quote">
  74                 I spent some time trying to figure out why my particular
  75                 DFS root wasn't working. I noted in the documentation that
  76                 the symlink should be in all lowercase. It should be
  77                 amended that the entire path to the symlink should all be
  78                 in lowercase as well.
  79                 </span>&#8221;</p><p>
  80                 &#8220;<span class="quote">For example, I had a share defined as such:</span>&#8221;
  81                 </p><table class="simplelist" border="0" summary="Simple list"><tr><td> </td></tr><tr><td><em class="parameter"><code>[pub]</code></em></td></tr><tr><td><a class="indexterm" name="id2625467"></a><em class="parameter"><code>path = /export/home/Shares/public_share</code></em></td></tr><tr><td><a class="indexterm" name="id2625480"></a><em class="parameter"><code>msdfs root = yes</code></em></td></tr></table><p>
  82                 &#8220;<span class="quote">and I could not make my Windows 9x/Me (with the dfs client installed) follow this symlink:</span>&#8221;
  83                 </p><pre class="screen">
  84                 damage1 -&gt; msdfs:damage\test-share
  85                 </pre><p>
  86                 </p><p>
  87                 &#8220;<span class="quote">Running a debug level of 10 reveals:</span>&#8221;
  88                 </p><pre class="programlisting">
  89                 [2003/08/20 11:40:33, 5] msdfs/msdfs.c:is_msdfs_link(176)
  90                   is_msdfs_link: /export/home/shares/public_share/* does not exist.
  91                 </pre><p>
  92                 &#8220;<span class="quote">Curious. So I changed the directory name from <code class="constant">.../Shares/...</code> to
  93                 <code class="constant">.../shares/...</code> (along with my service definition) and it worked!</span>&#8221;
  94                 </p></div></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="InterdomainTrusts.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="optional.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="classicalprinting.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 19. Interdomain Trust Relationships </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 21. Classical Printing Support</td></tr></table></div></body></html>