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diff --git a/slackbook/html/network-configuration-nfs.html b/slackbook/html/network-configuration-nfs.html deleted file mode 100644 index ca6138d8..00000000 --- a/slackbook/html/network-configuration-nfs.html +++ /dev/null @@ -1,308 +0,0 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" - "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> -<html xmlns="http://www.w3.org/1999/xhtml"> -<head> -<meta name="generator" content="HTML Tidy, see www.w3.org" /> -<title>Network File Systems</title> -<meta name="GENERATOR" content="Modular DocBook HTML Stylesheet Version 1.7" /> -<link rel="HOME" title="Slackware Linux Essentials" href="index.html" /> -<link rel="UP" title="Network Configuration" href="network-configuration.html" /> -<link rel="PREVIOUS" title="Wireless" href="network-configuration-wireless.html" /> -<link rel="NEXT" title="X Configuration" href="x-window-system.html" /> -<link rel="STYLESHEET" type="text/css" href="docbook.css" /> -<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /> -</head> -<body class="SECT1" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#840084" -alink="#0000FF"> -<div class="NAVHEADER"> -<table summary="Header navigation table" width="100%" border="0" cellpadding="0" -cellspacing="0"> -<tr> -<th colspan="3" align="center">Slackware Linux Essentials</th> -</tr> - -<tr> -<td width="10%" align="left" valign="bottom"><a -href="network-configuration-wireless.html" accesskey="P">Prev</a></td> -<td width="80%" align="center" valign="bottom">Chapter 5 Network Configuration</td> -<td width="10%" align="right" valign="bottom"><a href="x-window-system.html" -accesskey="N">Next</a></td> -</tr> -</table> - -<hr align="LEFT" width="100%" /> -</div> - -<div class="SECT1"> -<h1 class="SECT1"><a id="NETWORK-CONFIGURATION-NFS" name="NETWORK-CONFIGURATION-NFS">5.6 -Network File Systems</a></h1> - -<p>At this point, you should have a working TCP/IP connection to your network. You should -be able to ping other computers on your internal network and, if you have configured an -appropriate gateway, you should also be able to ping computers on the Internet itself. As -we know, the whole point in bringing a computer onto a network is to access information. -While some people might bring a computer up on a network just for the fun of it, most -people wish to be able to share files and printers. They wish to be able to access -documents on the Internet or play an online game. Having TCP/IP installed and functional -on your new Slackware system is a means to that end, but with just TCP/IP installed, -functionality will be very rudimentary. To share files, we will have to transfer them -back and forth using either FTP or SCP. We cannot browse files on our new Slackware -computer from the Network Neighborhood or My Network Places icons on Windows computers. -We'd like to be able to access files on other Unix machines seamlessly.</p> - -<p>Ideally, we'd like to be able to use a <span class="emphasis"><i -class="EMPHASIS">network file system</i></span> to allow us transparent access to our -files on other computers. The programs that we use to interact with information stored on -our computers really do not need to know on what computer a given file is stored; they -just need to know that it exists and how to get to it. It is then the responsibility of -the operating system to manage access to that file through the available file systems and -network file systems. The two most commonly used network file systems are SMB (as -implemented by Samba) and NFS.</p> - -<div class="SECT2"> -<h2 class="SECT2"><a id="NETWORK-CONFIGURATION-NSF-SMB" -name="NETWORK-CONFIGURATION-NSF-SMB">5.6.1 SMB/Samba/CIFS</a></h2> - -<p>SMB (for Server Message Block) is a descendant of the older NetBIOS protocol that was -initially used by IBM in their LAN Manager product. Microsoft has always been fairly -interested in NetBIOS and it's successors (NetBEUI, SMB and CIFS). The Samba project has -existed since 1991, when it was originally written to link an IBM PC running NetBIOS with -a Unix server. These days, SMB is the preferred method for sharing file and print -services over a network for virtually the entire civilized world because Windows supports -it.</p> - -<p>Samba's configuration file is <tt class="FILENAME">/etc/samba/smb.conf</tt>; one of -the most well commented and documented configuration files you will find anywhere. Sample -shares have been setup for you to view and modify for your needs. If you need even -tighter control the man page for smb.conf is indispensable. Since Samba is documented so -well in the places I've mentioned above, we will not rewrite the documentation here. We -will, however, quickly cover the basics.</p> - -<p><tt class="FILENAME">smb.conf</tt> is broken down into multiple sections: one section -per share, and a global section for setting options that are to be used everywhere. Some -options are only valid in the global section; some are only valid outside the global -section. Remember that the global section can be over-ridden by any other section. Refer -to the man pages for more information.</p> - -<p>You will most likely wish to edit your <tt class="FILENAME">smb.conf</tt> file to -reflect the network settings in your LAN. I would suggest modifying the items listed -below:</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="PROGRAMLISTING"> -[global] -# workgroup = NT-Domain-Name or Workgroup-Name, eg: LINUX2 -workgroup = MYGROUP -</pre> -</td> -</tr> -</table> - -<p>Change the workgroup name to reflect the workgroup or domain name that you are using -locally.</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="PROGRAMLISTING"> -# server string is the equivalent of the NT Description field -server string = Samba Server -</pre> -</td> -</tr> -</table> - -<p>This will be the name of your Slackware computer displayed in the Network Neighborhood -(or My Network Places) folder.</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="PROGRAMLISTING"> -# Security mode. Most people will want user level security. See -# security_level.txt for details. NOTE: To get the behaviour of -# Samba-1.9.18, you'll need to use "security = share". -security = user -</pre> -</td> -</tr> -</table> - -<p>You'll almost certainly wish to implement user level security on your Slackware -system.</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="PROGRAMLISTING"> -# You may wish to use password encryption. Please read -# ENCRYPTION.txt, Win95.txt and WinNT.txt in the Samba -# documentation. -# Do not enable this option unless you have read those documents -encrypt passwords = yes -</pre> -</td> -</tr> -</table> - -<p>If encrypt passwords is not enabled, you will not be able to use Samba with NT4.0, -Win2k, WinXP, and Win2003. Earlier Windows operating systems did not require encryption -to share files.</p> - -<p>SMB is an authenticated protocol, meaning you must supply a correct username and -password in order to use this service. We tell the samba server what usernames and -passwords are valid with the <tt class="COMMAND">smbpasswd</tt> command. <tt -class="COMMAND">smbpasswd</tt> takes a couple of common switches to tell it to either add -traditional users, or add machine users (SMB requires that you add the computers' NETBIOS -names as machine users, restricting what computers one can authenticate from).</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="SCREEN"> -Adding a user to the <tt class="FILENAME">/etc/samba/private/smbpasswd</tt> file. -<samp class="PROMPT">#</samp> <kbd class="USERINPUT">smbpasswd -a user</kbd> -Adding a machine name to the /etc/samba/private/smbpasswd file. -<samp class="PROMPT">#</samp> <kbd class="USERINPUT">smbpasswd -a -m machine</kbd> -</pre> -</td> -</tr> -</table> - -<p>It's important to note that a given username or machine name must already exist in the -<tt class="FILENAME">/etc/passwd</tt> file. You can accomplish this simply with the <tt -class="COMMAND">adduser</tt> command. Note that when using the <tt -class="COMMAND">adduser</tt> command to add a machine name one must append a dollar sign -(“<var class="LITERAL">$</var>”) to the machine name. This should <span -class="emphasis"><i class="EMPHASIS">not</i></span> however, be done with <tt -class="COMMAND">smbpasswd</tt>. <tt class="COMMAND">smbpasswd</tt> appends the dollar -sign on its own. Failing to mangle the machine name this way with <tt -class="COMMAND">adduser</tt> will result in an error when adding the machine name to -samba.</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="SCREEN"> -<samp class="PROMPT">#</samp> <kbd class="USERINPUT">adduser machine$</kbd> -</pre> -</td> -</tr> -</table> -</div> - -<div class="SECT2"> -<h2 class="SECT2"><a id="NETWORK-CONFIGURATION-NFS-NFS" -name="NETWORK-CONFIGURATION-NFS-NFS">5.6.2 Network File System (NFS)</a></h2> - -<p>NFS (or Network File System) was originally written by Sun for their Solaris -implementation of Unix. While it is significantly easier to get up and running when -compared to SMB, it is also significantly less secure. The primary insecurity in NFS is -that it is easy to spoof user and group id's from one machine to another. NFS is an -unauthenticated protocol. Future versions of the NFS protocol are being devised that -enhance security, but these are not common at the time of this writing.</p> - -<p>NFS configuration is governed by the <tt class="FILENAME">/etc/exports</tt> file. When -you load the default <tt class="FILENAME">/etc/exports</tt> file into an editor, you'll -see a blank file with a two line comment on top. We'll need to add a line to the exports -file for each directory that we wish to export, with a listing of client workstations -that will be allowed to access that file. For instance, if we wished to export directory -<tt class="FILENAME">/home/foo</tt> to workstation Bar, we would simply add the line:</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="PROGRAMLISTING"> -/home/foo Bar(rw) -</pre> -</td> -</tr> -</table> - -<p>to our <tt class="FILENAME">/etc/exports</tt>. Below, you'll find the example from the -man page for the <tt class="FILENAME">exports</tt> file:</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="PROGRAMLISTING"> -# sample /etc/exports file -/ master(rw) trusty(rw,no_root_squash) -/projects proj*.local.domain(rw) -/usr *.local.domain(ro) @trusted(rw) -/home/joe pc001(rw,all_squash,anonuid=150,anongid=100) -/pub (ro,insecure,all_squash) -</pre> -</td> -</tr> -</table> - -<p>As you can see, there are various options available, but most should be fairly clear -from this example.</p> - -<p>NFS works under the assumption that a given user on one machine in a network has the -same user ID on all machines across the network. When an attempt is made to read or write -from a NFS client to an NFS server, a UID is passed as part of the read/write request. -This UID is treated the same as if the read/write request originated on the local -machine. As you can see, if one could arbitrarily specify a given UID when accessing -resources on a remote system, Bad Things (tm) could and would happen. As a partial hedge -against this, each directory is mounted with the <var class="OPTION">root_squash</var> -option. This maps the UID for any user claiming to be root to a different UID, thus -preventing root access to the files or folders in the exported directory. <var -class="OPTION">root_squash</var> seems to be enabled by default as a security measure, -but the authors recommend specifying it anyway in your <tt -class="FILENAME">/etc/exports</tt> file.</p> - -<p>You can also export a directory directly from the command line on the server by using -the <tt class="COMMAND">exportfs</tt> command as follows:</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="SCREEN"> -<samp class="PROMPT">#</samp> <kbd -class="USERINPUT">exportfs -o rw,no_root_squash Bar:/home/foo</kbd> -</pre> -</td> -</tr> -</table> - -<p>This line exports the <tt class="FILENAME">/home/foo</tt> directory to the computer -“<tt class="HOSTID">Bar</tt>” and grants <tt class="HOSTID">Bar</tt> -read/write access. Additionally, the NFS server will not invoke <var -class="OPTION">root_squash</var>, which means any user on Bar with a UID of -“0” (root's UID) will have the same privileges as root on the server. The -syntax does look strange (usually when a directory is specified in <var -class="LITERAL">computer:/directory/file</var> syntax, you are referring to a file in a -directory on a given computer).</p> - -<p>You'll find more information on the man page for the exports file.</p> -</div> -</div> - -<div class="NAVFOOTER"> -<hr align="LEFT" width="100%" /> -<table summary="Footer navigation table" width="100%" border="0" cellpadding="0" -cellspacing="0"> -<tr> -<td width="33%" align="left" valign="top"><a href="network-configuration-wireless.html" -accesskey="P">Prev</a></td> -<td width="34%" align="center" valign="top"><a href="index.html" -accesskey="H">Home</a></td> -<td width="33%" align="right" valign="top"><a href="x-window-system.html" -accesskey="N">Next</a></td> -</tr> - -<tr> -<td width="33%" align="left" valign="top">Wireless</td> -<td width="34%" align="center" valign="top"><a href="network-configuration.html" -accesskey="U">Up</a></td> -<td width="33%" align="right" valign="top">X Configuration</td> -</tr> -</table> -</div> -</body> -</html> - |