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diff --git a/slackbook/html/network-configuration-tcpip.html b/slackbook/html/network-configuration-tcpip.html deleted file mode 100644 index 3b49437e..00000000 --- a/slackbook/html/network-configuration-tcpip.html +++ /dev/null @@ -1,324 +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>TCP/IP Configuration</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="Network Hardware Configuration" -href="network-configuration-hardware.html" /> -<link rel="NEXT" title="PPP" href="network-configuration-ppp.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-hardware.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="network-configuration-ppp.html" -accesskey="N">Next</a></td> -</tr> -</table> - -<hr align="LEFT" width="100%" /> -</div> - -<div class="SECT1"> -<h1 class="SECT1"><a id="NETWORK-CONFIGURATION-TCPIP" -name="NETWORK-CONFIGURATION-TCPIP">5.3 TCP/IP Configuration</a></h1> - -<p>At this point, your network card should be physically installed in your computer, and -the relevant kernel modules should be loaded. You will not yet be able to communicate -over your network card, but information about the network device can be obtained with <tt -class="COMMAND">ifconfig -a</tt>.</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="SCREEN"> -<samp class="PROMPT">#</samp> <kbd class="USERINPUT">ifconfig -a</kbd> -eth0 Link encap:Ethernet HWaddr 00:A0:CC:3C:60:A4 -UP BROADCAST NOTRAILERS RUNNING MULTICAST MTU:1500 Metric:1 -RX packets:110081 errors:1 dropped:0 overruns:0 frame:0 -TX packets:84931 errors:0 dropped:0 overruns:0 carrier:0 -collisions:0 txqueuelen:100 -RX bytes:114824506 (109.5 Mb) TX bytes:9337924 (8.9 Mb) -Interrupt:5 Base address:0x8400 - -lo Link encap:Local Loopback -inet addr:127.0.0.1 Mask:255.0.0.0 -UP LOOPBACK RUNNING MTU:16436 Metric:1 -RX packets:2234 errors:0 dropped:0 overruns:0 frame:0 -TX packets:2234 errors:0 dropped:0 overruns:0 carrier:0 -collisions:0 txqueuelen:0 -RX bytes:168758 (164.8 Kb) TX bytes:168758 (164.8 Kb) -</pre> -</td> -</tr> -</table> - -<p>If you just typed <tt class="COMMAND">/sbin/ifconfig</tt> without the <var -class="OPTION">-a</var> suffix, you would not see the <tt class="FILENAME">eth0</tt> -interface, as your network card does not yet have a valid IP address or route.</p> - -<p>While there are many different ways to setup and subnet a network, all of them can be -broken down into two types: Static and Dynamic. Static networks are setup such that each -node (geek lingo for thing with an IP address) always has the same IP address. Dynamic -networks are setup in such a way that the IP addresses for the nodes are controlled by a -single server called the DHCP server.</p> - -<div class="SECT2"> -<h2 class="SECT2"><a id="NETWORK-CONFIGURATION-TCPIP-DHCP" -name="NETWORK-CONFIGURATION-TCPIP-DHCP">5.3.1 DHCP</a></h2> - -<p>DHCP (or Dynamic Host Configuration Protocol), is a means by which an IP address may -be assigned to a computer on boot. When the DHCP <span class="emphasis"><i -class="EMPHASIS">client</i></span> boots, it puts out a request on the Local Area Network -for a DHCP <span class="emphasis"><i class="EMPHASIS">server</i></span> to assign it an -IP address. The DHCP server has a pool (or <span class="emphasis"><i -class="EMPHASIS">scope</i></span>) of IP addresses available. The server will respond to -this request with an IP address from the pool, along with a <span class="emphasis"><i -class="EMPHASIS">lease time</i></span>. Once the lease time for a given IP address lease -has expired, the client must contact the server again and repeat the negotiation.</p> - -<p>The client will then accept the IP address from the server and will configure the -requested interface with the IP address. There is one more handy trick that DHCP clients -use for negotiating the IP address that they will be assigned, however. The client will -remember it's last assigned IP address, and will request that the server re-assign that -IP address to the client again upon next negotiation. If possible, the server will do so, -but if not, a new address is assigned. So, the negotiation resembles the following:</p> - -<p class="LITERALLAYOUT"> <span class="emphasis"><i -class="EMPHASIS">Client</i></span>: Is there a DHCP server available on the LAN?<br /> - - <span class="emphasis"><i -class="EMPHASIS">Server</i></span>: Yes, there is. Here I am.<br /> - - <span class="emphasis"><i -class="EMPHASIS">Client</i></span>: I need an IP address.<br /> - <span class="emphasis"><i -class="EMPHASIS">Server</i></span>: You may take 192.168.10.10 for 19200 seconds.<br /> - - <span class="emphasis"><i -class="EMPHASIS">Client</i></span>: Thank you.</p> - -<p class="LITERALLAYOUT"> <span class="emphasis"><i -class="EMPHASIS">Client</i></span>: Is there a DHCP server available on the LAN?<br /> - - <span class="emphasis"><i -class="EMPHASIS">Server</i></span>:Yes, there is. Here I am.<br /> - - <span class="emphasis"><i -class="EMPHASIS">Client</i></span>:I need an IP address. The last time we<br /> - - talked, I had 192.168.10.10;<br /> - May I have it again?<br /> - <span class="emphasis"><i -class="EMPHASIS">Server</i></span>:Yes, you may (or No, you may not: take 192.168.10.12 instead).<br /> - - <span class="emphasis"><i -class="EMPHASIS">Client</i></span>: Thank you.</p> - -<p>The DHCP client in Linux is <tt class="COMMAND">/sbin/dhcpcd</tt>. If you load <tt -class="FILENAME">/etc/rc.d/rc.inet1</tt> in your favorite text editor, you will notice -that <tt class="COMMAND">/sbin/dhcpcd</tt> is called about midway through the script. -This will force the conversation shown above. <tt class="COMMAND">dhcpcd</tt> will also -track the amount of time left on the lease for the current IP address, and will -automatically contact the DHCP server with a request to renew the lease when necessary. -DHCP can also control related information, such as what ntp server to use, what route to -take, etc.</p> - -<p>Setting up DHCP on Slackware is simple. Just run <tt class="COMMAND">netconfig</tt> -and select DHCP when offered. If you have more than one NIC and do not wish <tt -class="FILENAME">eth0</tt> to be configured by DHCP, just edit the <tt -class="FILENAME">/etc/rc.d/rc.inet1.conf</tt> file and change the related variable for -your NIC to “<var class="LITERAL">YES</var>”.</p> -</div> - -<div class="SECT2"> -<h2 class="SECT2"><a id="NETWORK-CONFIGURATION-TCPIP-STATIC" -name="NETWORK-CONFIGURATION-TCPIP-STATIC">5.3.2 Static IP</a></h2> - -<p>Static IP addresses are fixed addresses that only change if manually told to. These -are used in any case where an administrator doesn't want the IP information to change, -such for internal servers on a LAN, any server connected to the Internet, and networked -routers. With static IP addressing, you assign an address and leave it at that. Other -machines know that you are always at that certain IP address and can contact you at that -address always.</p> -</div> - -<div class="SECT2"> -<h2 class="SECT2"><a id="NETWORK-CONFIGURATION-TCPIP-CONF" -name="NETWORK-CONFIGURATION-TCPIP-CONF">5.3.3 <tt -class="FILENAME">/etc/rc.d/rc.inet1.conf</tt></a></h2> - -<p>If you plan on assigning an IP address to your new Slackware box, you may do so either -through the <tt class="FILENAME">netconfig</tt> script, or you may edit <tt -class="FILENAME">/etc/rc.d/rc.inet1.conf</tt>. In <tt -class="FILENAME">/etc/rc.d/rc.inet1.conf</tt> , you will notice:</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="PROGRAMLISTING"> - # Primary network interface card (eth0) - IPADDR[0]="" - NETMASK[0]="" - USE_DHCP[0]="" - DHCP_HOSTNAME[0]="" -</pre> -</td> -</tr> -</table> - -<p>Then further at the bottom:</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="PROGRAMLISTING"> - GATEWAY="" -</pre> -</td> -</tr> -</table> - -<p>In this case, our task is merely to place the correct information between the -double-quotes. These variables are called by <tt class="FILENAME">/etc/rc.d/rc.inet1</tt> -at boot time to setup the nics. For each NIC, just enter the correct IP information, or -put “<var class="LITERAL">YES</var>” for <var class="LITERAL">USE_DHCP</var>. -Slackware will startup the interfaces with the information placed here in the order they -are found.</p> - -<p>The <var class="LITERAL">DEFAULT_GW</var> variable sets up the default route for -Slackware. All communications between your computer and other computers on the Internet -must pass through that gateway if no other route is specified for them. If you are using -DHCP, you will usually not need to enter anything here, as the DHCP server will specify -what gateway to use.</p> -</div> - -<div class="SECT2"> -<h2 class="SECT2"><a id="NETWORK-CONFIGURATION-TCPIP-RESOLVER" -name="NETWORK-CONFIGURATION-TCPIP-RESOLVER">5.3.4 <tt -class="FILENAME">/etc/resolv.conf</tt></a></h2> - -<p>Ok, so you've got an IP address, you've got a default gateway, you may even have ten -million dollars (give us some), but what good is that if you can't resolve names to IP -addresses? No one wants to type in <tt class="HOSTID">72.9.234.112</tt> into their web -browser to reach <tt class="HOSTID">www.slackbook.org</tt>. After all, who other than the -authors would memorize that IP address? We need to setup DNS, but how? That's where <tt -class="FILENAME">/etc/resolv.conf</tt> comes into play.</p> - -<p>Chances are you already have the proper options in <tt -class="FILENAME">/etc/resolv.conf</tt>. If you setup your network connection using DHCP, -the DHCP server should handle updating this file for you. (Technically the DHCP server -just tells <tt class="COMMAND">dhcpcd</tt> what to put here, and it obeys.) If you need -to manually update your DNS server list though, you'll need to hand edit <tt -class="FILENAME">/etc/resolv.conf</tt>. Below is an example:</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="SCREEN"> -<samp class="PROMPT">#</samp> <kbd class="USERINPUT">cat /etc/resolv.conf</kbd> -nameserver 192.168.1.254 -search lizella.net -</pre> -</td> -</tr> -</table> - -<p>The first line is simple. The nameserver directive tells us what DNS servers to query. -By necessity these are always IP addresses. You may have as many listed there as you -like. Slackware will happily check one after the other until one returns a match.</p> - -<p>The second line is a little more interesting. The search directive gives us a list of -domain names to assume whenever a DNS request is made. This allows you to contact a -machine by only the first part of its FQDN (Fully Qualified Domain Name). For example, if -“slackware.com” were in your search path, you could reach <tt -class="HOSTID">http://store.slackware.com</tt> by just pointing your web browser at <tt -class="HOSTID">http://store</tt>.</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="SCREEN"> -<samp class="PROMPT">#</samp> <kbd class="USERINPUT">ping -c 1 store</kbd> -PING store.slackware.com (69.50.233.153): 56 data bytes -64 bytes from 69.50.233.153 : icmp_seq=0 ttl=64 time=0.251 ms -1 packets transmitted, 1 packets received, 0% packet loss -round-trip min/avg/max = 0.251/0.251/0.251 ms -</pre> -</td> -</tr> -</table> - -<br /> -<br /> -</div> - -<div class="SECT2"> -<h2 class="SECT2"><a id="NETWORK-CONFIGURATION-TCPIP-HOSTS" -name="NETWORK-CONFIGURATION-TCPIP-HOSTS">5.3.5 <tt -class="FILENAME">/etc/hosts</tt></a></h2> - -<p>Now that we've got DNS working fine, what if we want to bypass our DNS server, or add -a DNS entry for a machine that isn't in DNS? Slackware includes the oft-loved <tt -class="FILENAME">/etc/hosts</tt> file which contains a local list of DNS names and IP -addresses they should match to.</p> - -<table border="0" bgcolor="#E0E0E0" width="100%"> -<tr> -<td> -<pre class="SCREEN"> -<samp class="PROMPT">#</samp> <kbd class="USERINPUT">cat /etc/hosts</kbd> -127.0.0.1 localhost locahost.localdomain -192.168.1.101 redtail -172.14.66.32 foobar.slackware.com -</pre> -</td> -</tr> -</table> - -<p>Here you can see that localhost has an IP address of <tt class="HOSTID">127.0.0.1</tt> -(always reserved for localhost), redtail can be reached at <tt -class="HOSTID">192.168.1.101</tt>, and <tt class="HOSTID">foobar.slackware.com</tt> is -<tt class="HOSTID">172.14.66.32</tt>.</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-hardware.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="network-configuration-ppp.html" -accesskey="N">Next</a></td> -</tr> - -<tr> -<td width="33%" align="left" valign="top">Network Hardware Configuration</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">PPP</td> -</tr> -</table> -</div> -</body> -</html> - |