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Bring the first part of the ppp documentation up to date, more to come.

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@ -1,7 +1,7 @@
<!--
The FreeBSD Documentation Project
$FreeBSD: doc/en_US.ISO8859-1/books/handbook/ppp-and-slip/chapter.sgml,v 1.47 2001/08/11 21:34:52 jim Exp $
$FreeBSD: doc/en_US.ISO8859-1/books/handbook/ppp-and-slip/chapter.sgml,v 1.48 2001/08/15 00:51:25 logo Exp $
-->
<chapter id="ppp-and-slip">
@ -53,11 +53,13 @@
the already existing kernel implementation of PPP.</para>
<para>You may be wondering what the main difference is between User
PPP and kernel PPP. The answer is simple; user PPP does not run as
a daemon, and can run as and when desired. No PPP interface needs
to be compiled into their kernel; it runs as a user process, and uses
the tunnel device driver (<devicename>tun</devicename>) to get data
into and out of the kernel.</para>
PPP and kernel PPP. The answer is simple; user PPP processes the
inbound and outbound data in userland rather than in the kernel.
This is expensive in terms of copying the data between the kernel
and userland, but allows a far more feature-rich ppp implementation.
User PPP uses the <devicename>tun</devicename> device to communicate
with the outside world whereas kernel-ppp uses the
<devicename>ppp</devicename> device.</para>
<para>From here on out in this chapter, user ppp will simply be
referred to as ppp unless a distinction needs to be made between it
@ -151,7 +153,8 @@
you can use the <command>enable dns</command> command in
your <filename>ppp.conf</filename> file to tell
<application>ppp</application> to set the name servers for
you.</para>
you. This feature depends on your ISPs PPP implementation
supporting DNS negotiation.</para>
</listitem>
</itemizedlist>
@ -174,7 +177,7 @@
<listitem>
<para>The netmask you should use. If your ISP has not
provided you with one, you can safely use <hostid
role="netmask">255.255.255.0</hostid>.</para>
role="netmask">255.255.255.255</hostid>.</para>
</listitem>
<indexterm id="ppp-statis-ip">
@ -195,85 +198,37 @@
<title>Preparing the Kernel</title>
<para>As previously mentioned, <application>ppp</application>
uses the <devicename>tun</devicename> device, and whichever kernel
you are using must have <devicename>tun</devicename> configured.
The <devicename>tun</devicename> device is preconfigured
for the default <filename>GENERIC</filename> kernel that ships
with FreeBSD. However, if you have installed a custom kernel,
you must make sure your kernel is configured for ppp.</para>
uses the <devicename>tun</devicename> device. If this device
has not been compiled into your kernel,
<application>ppp</application> will load it on demand as a
module. The tunnel driver is dynamic, so any number of
devices may be created (you are not limited by any kernel
configuration values).</para>
<indexterm id="ppp-kernel-compilation">
<primary>kernel</primary>
<secondary>compiling</secondary>
</indexterm>
<para>To check, go to your kernel compile directory
(<filename>/sys/i386/conf</filename> or
<filename>/sys/pc98/conf</filename>) and examine your
configuration file. It should have the following line somewhere
in it:</para>
<note>It should be noted that the tunnel driver creates devices
on demand, so <command>ifconfig -a</command> won't necessarily
show up with any <devicename>tun</devicename> devices.</note>
<programlisting>pseudo-device tun 1</programlisting>
<para>If this line is not present, you will need to add it to the
configuration file and recompile your kernel. The stock
<filename>GENERIC</filename> kernel has this included, so if you
have not installed a custom kernel or do not have a
<filename>/sys</filename> directory, you do not have to change
anything. If you do need to recompile your kernel, please refer
to the <link linkend="kernelconfig">kernel configuration</link>
section for more information.</para>
<para>You can check how many tunnel devices your current kernel
has by typing the following:</para>
<screen>&prompt.root; <userinput>ifconfig -a</userinput>
tun0: flags=8051&lt;UP,POINTOPOINT,RUNNING,MULTICAST&gt; mtu 1500
inet 200.10.100.1 --&gt; 203.10.100.24 netmask 0xffffffff
tun1: flags=8050&lt;POINTOPOINT,RUNNING,MULTICAST&gt; mtu 576
tun2: flags=8051&lt;UP,POINTOPOINT,RUNNING,MULTICAST&gt; mtu 1500
inet 203.10.100.1 --&gt; 203.10.100.20 netmask 0xffffffff
tun3: flags=8010&lt;POINTOPOINT,MULTICAST&gt; mtu 1500</screen>
<note>
<para>In FreeBSD 4.0 and later releases, you will only see any
<devicename>tun</devicename> devices which have already been
used. This means you might not see <emphasis>any</emphasis>
<devicename>tun</devicename> devices. If this is the case, do
not worry; the device should be created dynamically when
<command>ppp</command> attempts to use it.</para>
</note>
<para>This case shows four tunnel devices, two of which are
currently configured and being used. It should be noted that
the <literal>RUNNING</literal> flag above indicates that the
interface has been used at some point&mdash;it is not an error
if your interface does not show up as
<literal>RUNNING</literal>.</para>
<para>If for some reason you have a kernel that does not have the
<devicename>tun</devicename> device in it and cannot recompile
the kernel, all is not lost. You should be able to dynamically
load the code. Please refer to the appropriate
&man.modload.8; and &man.lkm.4; manual pages for further
details.</para>
</sect3>
<sect3>
<title>Check the <devicename>tun</devicename> Device</title>
<para>Under normal circumstances, most users will only require one
<para>Under normal circumstances, most users will only use one
<devicename>tun</devicename> device
(<filename>/dev/tun0</filename>). If you have specified more
than one on the <literal>pseudo-device</literal> line for
<devicename>tun</devicename> in your kernel configuration file,
then alter all references to <devicename>tun0</devicename> below
to reflect whichever device number you are using (e.g.,
<devicename>tun2</devicename>).</para>
(<filename>/dev/tun0</filename>). References to
<devicename>tun0</devicename> below may be changed to
<devicename>tunN</devicename> where N is any unit number.</para>
<para>For FreeBSD installations that do not have DEVFS enabled,
the existence of the <devicename>tun0</devicename> device should
be verified (this is not necessary if DEVFS is enabled as device
nodes will be created on demand).
<para>The easiest way to make sure that the
<devicename>tun0</devicename> device is configured correctly,
is to remake the device. This process is quite easy. To remake
the device, do the following:</para>
is to remake the device. To remake the device, do the
following:</para>
<screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>./MAKEDEV tun0</userinput></screen>
@ -284,22 +239,6 @@ tun3: flags=8010&lt;POINTOPOINT,MULTICAST&gt; mtu 1500</screen>
<screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>./MAKEDEV tun15</userinput></screen>
<para>To confirm that the kernel is configured correctly, issue
the follow command and compare the results:</para>
<screen>&prompt.root; <userinput>ifconfig tun0</userinput>
tun0: flags=8050&lt;POINTOPOINT,RUNNING,MULTICAST&gt; mut 1500</screen>
<para>The <literal>RUNNING</literal> flag may not yet be set, in
which case you will see:</para>
<screen>&prompt.root; <userinput>ifconfig tun0</userinput>
tun0: flags=8010&lt;POINTOPOINT,MULTICAST&gt; mtu 1500</screen>
<para>Remember from earlier that you might not see the device if it
has not been used yet, as <devicename>tun</devicename> devices are
created on demand in FreeBSD 4.0 and later releases.</para>
</sect3>
<sect3>
@ -324,23 +263,34 @@ tun0: flags=8010&lt;POINTOPOINT,MULTICAST&gt; mtu 1500</screen>
beyond the scope of this document.</para>
<para>The resolver is a set of system calls that do the name
mappings, but you have to tell them where to find their
information. You do this by first editing the file
<filename>/etc/host.conf</filename>. Do <emphasis>not</emphasis>
call this file <filename>/etc/hosts.conf</filename> (note the
extra <literal>s</literal>) as the results can be
confusing.</para>
mappings, but you have to tell it where to find the
information. For versions of FreeBSD prior to 5.0, you do this
by first editing the file <filename>/etc/host.conf</filename>.
FreeBSD 5.0 uses the <filename>/etc/nsswitch.conf</filename> file.
<sect4>
<title>Edit <filename>/etc/host.conf</filename></title>
<para>This file should contain the following two lines (in this
order):</para>
<para>For versions of FreeBSD prior to 5.0, this file should
contain the following two lines (in this order):</para>
<programlisting>hosts
bind</programlisting>
<para>These instruct the resolver to first look in the file
<para>This instructs the resolver to first look in the file
<filename>/etc/hosts</filename>, and then to consult the DNS
if the name was not found.</para>
</sect4>
<sect4>
<title>Edit <filename>/etc/nsswitch.conf</filename></title>
<para>For FreeBSD version 5.0 or above, this file should
contain at least the following line:
<programlisting>hosts: files, dns</programlisting>
<para>This instructs the resolver to first look in the file
<filename>/etc/hosts</filename>, and then to consult the DNS
if the name was not found.</para>
</sect4>
@ -348,7 +298,7 @@ bind</programlisting>
<sect4>
<title>Edit <filename>/etc/hosts</filename></title>
<para>This file should contain the IP addresses and names of
<para>This file may contain the IP addresses and names of
machines on your network. At a bare minimum it should contain
entries for the machine which will be running ppp. Assuming
that your machine is called <hostid
@ -357,30 +307,29 @@ bind</programlisting>
<filename>/etc/hosts</filename> should contain:</para>
<programlisting>127.0.0.1 localhost.bar.com localhost
127.0.0.1 localhost.bar.com.
10.0.0.1 foo.bar.com foo
10.0.0.1 foo.bar.com.</programlisting>
::1 localhost.bar.com localhost
10.0.0.1 foo.bar.com foo</programlisting>
<para>The first two lines define the alias
<hostid>localhost</hostid> as a synonym for the current
machine. Regardless of your own IP address, the IP address
for this line should always be <hostid
role="ipaddr">127.0.0.1</hostid>. The second two lines map
machine. Regardless of your own IP address, the IP addresses
for these lines should always be <hostid
role="ipaddr">127.0.0.1</hostid> and <hostid
role="ipaddr">::1</hostid>. The last line maps
the name <hostid role="fqdn">foo.bar.com</hostid> (and the
shorthand <hostid>foo</hostid>) to the IP address <hostid
role="ipaddr">10.0.0.1</hostid>.</para>
<para>If your provider allocates you a static IP address and
name, use them in place of the <hostid
role="ipaddr">10.0.0.1</hostid> entry.</para>
name, and you are not using that as your host name, add this
to the <filename>/etc/hosts</filename> too.
</sect4>
<sect4>
<title>Edit <filename>/etc/resolv.conf</filename></title>
<para>The <filename>/etc/resolv.conf</filename> file tells the
resolver how to behave. If you are running your own DNS, you
may leave this file empty. Normally, you will need to enter
resolver how to behave. Normally, you will need to enter
the following line(s):</para>
<programlisting>domain <replaceable>bar.com</replaceable>
@ -392,19 +341,23 @@ nameserver <replaceable>y.y.y.y</replaceable></programlisting>
<hostid role="ipaddr"><replaceable>y.y.y.y</replaceable></hostid>
addresses are those given to you by your ISP. Add as many
<literal>nameserver</literal> lines as your ISP provides. The
<literal>domain</literal> line defaults to your hostname's
domain, and is probably unnecessary. Refer to the
&man.resolv.conf.5; manual page for details of other possible
entries in this file.</para>
<literal>domain</literal> line is set to your hosts
domain name. Refer to the &man.resolv.conf.5; manual page for
details of other possible entries in this file.</para>
<para>If you are running a local name server, replace the
above nameserver lines with:</para>
<programlisting>nameserver <replaceable>0.0.0.0</replaceable></programlisting>
<indexterm><primary>PPP</primary></indexterm>
<indexterm><primary>ISP</primary></indexterm>
<para>If you are running PPP version 2 or greater, the
<command>enable dns</command> command will tell PPP to request
that your ISP confirms the nameserver values. If your ISP
supplies different addresses (or if there are no nameserver
lines in <filename>/etc/resolv.conf</filename>), PPP will
rewrite the file with the ISP-supplied values.</para>
<para>The <command>enable dns</command> command (entered in the
<filename>/etc/ppp/ppp.conf</filename> file - see below) will
tell PPP to request that your ISP confirms the nameserver values.
If your ISP supplies different addresses (or if there are no
nameserver lines in <filename>/etc/resolv.conf</filename>), PPP
will rewrite the file with the ISP-supplied values.</para>
</sect4>
</sect3>
@ -414,9 +367,9 @@ nameserver <replaceable>y.y.y.y</replaceable></programlisting>
<indexterm><primary>PPP</primary><secondary>configuration</secondary></indexterm>
<para>Both <command>ppp</command> and <command>pppd</command>
(the kernel level implementation of PPP) use the configuration
files located in the <filename>/usr/share/examples/ppp</filename> directory.
The sample configuration files provided are a good reference,
so do not delete them.</para>
files located in the <filename>/etc/ppp</filename> directory.
Examples for user ppp can be found in
<filename>/usr/share/examples/ppp/</filename>.
<para>Configuring <command>ppp</command> requires that you edit a
number of files, depending on your requirements. What you put
@ -429,9 +382,9 @@ nameserver <replaceable>y.y.y.y</replaceable></programlisting>
<title>PPP and Static IP Addresses</title>
<indexterm><primary>PPP</primary><secondary>with static IP addresses</secondary></indexterm>
<para>You will need to create a configuration file called
<filename>/etc/ppp/ppp.conf</filename>. It should look
similar to the example below.</para>
<para>You will need to edit the
<filename>/etc/ppp/ppp.conf</filename> configuration file. It
should look similar to the example below.</para>
<note>
<para>Lines that end in a <literal>:</literal> start in the
@ -440,16 +393,23 @@ nameserver <replaceable>y.y.y.y</replaceable></programlisting>
</note>
<programlisting>1 default:
2 set device /dev/cuaa0
3 set speed 115200
4 set dial "ABORT BUSY ABORT NO\\sCARRIER TIMEOUT 5 \"\" ATE1Q0 OK-AT-OK \\dATDT\\TTIMEOUT 40 CONNECT"
5 provider:
6 set phone "(123) 456 7890"
7 set login "TIMEOUT 10 \"\" \"\" gin:--gin: foo word: bar col: ppp"
8 set timeout 300
9 set ifaddr <replaceable>x.x.x.x</replaceable> <replaceable>y.y.y.y</replaceable> 255.255.255.0 0.0.0.0
10 add default HISADDR
11 enable dns</programlisting>
2 set log Phase Chat LCP IPCP CCP tun command
3 ident user-ppp VERSION (built COMPILATIONDATE)
4 set device /dev/cuaa0
5 set speed 115200
6 set dial "ABORT BUSY ABORT NO\\sCARRIER TIMEOUT 5 \
7 \"\" AT OK-AT-OK ATE1Q0 OK \\dATDT\\TTIMEOUT 40 CONNECT"
8 set timeout 180
9 enable dns
10
11 provider:
12 set phone "(123) 456 7890"
13 set authname foo
14 set authkey bar
15 set login "TIMEOUT 10 \"\" \"\" gin:--gin: \\U word: \\P col: ppp"
16 set timeout 300
17 set ifaddr <replaceable>x.x.x.x</replaceable> <replaceable>y.y.y.y</replaceable> 255.255.255.255 0.0.0.0
18 add default HISADDR</programlisting>
<para>Do not include the line numbers, they are just for
reference in this discussion.</para>
@ -467,6 +427,32 @@ nameserver <replaceable>y.y.y.y</replaceable></programlisting>
<varlistentry>
<term>Line 2:</term>
<listitem>
<para>Enables logging parameters. When the configuration
is working satisfactorily, this line should be reduced
to saying
<programlisting>set log phase tun</programlisting>
in order to avoid excessive log file sizes.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Line 3:</term>
<listitem>
<para>Tells PPP how to identify itself to the peer.
PPP identifies itself to the peer if it has any trouble
negotiating and setting up the link, providing information
that the peers administrator may find useful when
investigating such problems.
</listitem>
</varlistentry>
<varlistentry>
<term>Line 4:</term>
<listitem>
<para>Identifies the device to which the modem is
connected. <devicename>COM1</devicename> is
@ -477,7 +463,7 @@ nameserver <replaceable>y.y.y.y</replaceable></programlisting>
</varlistentry>
<varlistentry>
<term>Line 3:</term>
<term>Line 5:</term>
<listitem>
<para>Sets the speed you want to connect at. If 115200
@ -487,7 +473,7 @@ nameserver <replaceable>y.y.y.y</replaceable></programlisting>
</varlistentry>
<varlistentry>
<term>Line 4:</term>
<term>Line 6 & 7:</term>
<indexterm><primary>PPP</primary><secondary>user PPP</secondary></indexterm>
<listitem>
@ -495,11 +481,44 @@ nameserver <replaceable>y.y.y.y</replaceable></programlisting>
syntax similar to the &man.chat.8; program. Refer to
the manual page for information on the features of this
language.</para>
<para>Note that this command continues onto the next line
for readability. Any command in
<filename>ppp.conf</filename> may do this if the last
character on the line is a ``\'' character.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Line 5:</term>
<term>Line 8:</term>
<listitem>
<para>Sets the idle timeout for the link. 180 seconds
is the default, so this line is purely cosmetic.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Line 9:</term>
<listitem>
<para>Tells PPP to ask the peer to confirm the local
resolver settings. If you run a local name server, this
line should be commented out or removed.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Line 10:</term>
<listitem>
<para>A blank line for readability. Blank lines are ignored
by PPP.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Line 11:</term>
<listitem>
<para>Identifies an entry for a provider called
@ -508,7 +527,7 @@ nameserver <replaceable>y.y.y.y</replaceable></programlisting>
</varlistentry>
<varlistentry>
<term>Line 6:</term>
<term>Line 12:</term>
<listitem>
<para>Sets the phone number for this provider. Multiple
@ -525,10 +544,29 @@ nameserver <replaceable>y.y.y.y</replaceable></programlisting>
</varlistentry>
<varlistentry>
<term>Line 7:</term>
<term>Line 13 & 14:</term>
<listitem>
<para>The login string is of the same chat-like syntax as
<para>Identifies the user name and password. When connecting
using a unix-style login prompt, these values are referred
to by the <command>set login</command> command using the \U
and \P variables. When connecting using PAP or CHAP, these
values are used at authentication time.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Line 15:</term>
<listitem>
<indexterm><primary>PAP</primary></indexterm>
<indexterm><primary>CHAP</primary></indexterm>
<para>If you are using PAP or CHAP, there will be no login
at this point, and this line should be commented out or
removed. See <link linkend="userppp-PAPnCHAP">PAP and CHAP
authentication</link> for further details.</para>
<para>The login string is of the same chat-like syntax as
the dial string. In this example, the string works for
a service whose login session looks like this:</para>
@ -539,31 +577,27 @@ protocol: ppp</screen>
<para>You will need to alter this script to suit your own
needs. When you write this script for the first time,
you should enable <quote>chat</quote> logging to ensure
that the conversation is going as expected.</para>
<indexterm><primary>PAP</primary></indexterm>
<indexterm><primary>CHAP</primary></indexterm>
<para>If you are using PAP or CHAP, there will be no login
at this point, so your login string can be left blank.
See <link linkend="userppp-PAPnCHAP">PAP and CHAP
authentication</link> for further details.</para>
you should ensure that you have enabled <quote>chat</quote>
logging so you can determine if the conversation is going
as expected.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Line 8:</term>
<term>Line 16:</term>
<indexterm><primary>timeout</primary></indexterm>
<listitem>
<para>Sets the default timeout (in seconds) for the
<para>Sets the default idle timeout (in seconds) for the
connection. Here, the connection will be closed
automatically after 300 seconds of inactivity. If you
never want to timeout, set this value to zero.</para>
never want to timeout, set this value to zero or use
the <option>-ddial</option> command line switch.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Line 9:</term>
<term>Line 17:</term>
<indexterm><primary>ISP</primary></indexterm>
<listitem>
<para>Sets the interface addresses. The string
@ -580,13 +614,12 @@ protocol: ppp</screen>
instructions for <link linkend="userppp-dynamicIP">PPP
and Dynamic IP addresses</link>. If this line is
omitted, <command>ppp</command> cannot run in
<option>-auto</option> or <option>-dynamic</option>
mode.</para>
<option>-auto</option> mode.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Line 10:</term>
<term>Line 18:</term>
<listitem>
<para>Adds a default route to your ISP's gateway. The
@ -595,31 +628,24 @@ protocol: ppp</screen>
important that this line appears after line 9,
otherwise <literal>HISADDR</literal> will not yet be
initialized.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Line 11:</term>
<indexterm><primary>nameserver</primary></indexterm>
<listitem>
<para>This line tells PPP to ask your ISP to confirm that
your nameserver addresses are correct. If your ISP
supports this facility, PPP can then update
<filename>/etc/resolv.conf</filename> with the correct
nameserver entries.</para>
<para>If you do not wish to run ppp in <option>-auto</option>,
this line should be moved to the
<filename>ppp.linkup</filename> file.
</listitem>
</varlistentry>
</variablelist>
<para>It is not necessary to add an entry to
<filename>ppp.linkup</filename> when you have a static IP
address as your routing table entries are already correct
before you connect. You may however wish to create an entry
to invoke programs after connection. This is explained later
with the sendmail example.</para>
address and are running ppp in <option>-auto</option> mode as your
routing table entries are already correct before you connect.
You may however wish to create an entry to invoke programs after
connection. This is explained later with the sendmail
example.</para>
<para>Example configuration files can be found in the
<filename>/usr/share/examples/ppp</filename> directory.</para>
<filename>/usr/share/examples/ppp/</filename> directory.</para>
</sect4>
<sect4 id="userppp-dynamicIP">
@ -636,15 +662,15 @@ protocol: ppp</screen>
<link linkend="userppp-staticIP">PPP and Static IP
Addresses</link>, with the following change:</para>
<programlisting>9 set ifaddr 10.0.0.1/0 10.0.0.2/0 255.255.255.0</programlisting>
<programlisting>17 set ifaddr 10.0.0.1/0 10.0.0.2/0 255.255.255.255</programlisting>
<para>Again, do not include the line numbers, they are just for
<para>Again, do not include the line number, it is just for
reference. Indentation of at least one space is
required.</para>
<variablelist>
<varlistentry>
<term>Line 9:</term>
<term>Line 17:</term>
<listitem>
<para>The number after the <literal>/</literal> character
@ -654,28 +680,27 @@ protocol: ppp</screen>
will always work.</para>
<para>The last argument (<literal>0.0.0.0</literal>) tells
PPP to negotiate using address <hostid
PPP to start negotiations using address <hostid
role="ipaddr">0.0.0.0</hostid> rather than <hostid
role="ipaddr">10.0.0.1</hostid>. Do not use
<literal>0.0.0.0</literal> as the first argument to
<command>set ifaddr</command> as it prevents PPP from
setting up an initial route in <option>-auto</option>
mode.</para>
role="ipaddr">10.0.0.1</hostid> and is necessary for some
ISPs. Do not use <literal>0.0.0.0</literal> as the first
argument to <command>set ifaddr</command> as it prevents
PPP from setting up an initial route in
<option>-auto</option> mode.</para>
</listitem>
</varlistentry>
</variablelist>
<para>If you are running version 1.x of PPP, you will also need
to create an entry in <filename>/etc/ppp/ppp.linkup</filename>.
<para>If you are not running in <option>-auto</option> mode, you
will need to create an entry in
<filename>/etc/ppp/ppp.linkup</filename>.
<filename>ppp.linkup</filename> is used after a connection has
been established. At this point, <command>ppp</command> will
know what IP addresses should <emphasis>really</emphasis> be
used. The following entry will delete the existing bogus
routes, and create correct ones:</para>
have assigned the interface addresses and it will now be
possible to add the routing table entries:</para>
<programlisting>1 provider:
2 delete ALL
3 add 0 0 HISADDR</programlisting>
2 add default HISADDR</programlisting>
<variablelist>
<varlistentry>
@ -697,22 +722,11 @@ protocol: ppp</screen>
<varlistentry>
<term>Line 2:</term>
<listitem>
<para>This line tells <command>ppp</command> to delete all
of the existing routes for the acquired
<devicename>tun</devicename> interface (except the
direct route entry).</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Line 3:</term>
<listitem>
<para>This line tells <command>ppp</command> to add a
default route that points to <literal>HISADDR</literal>.
<literal>HISADDR</literal> will be replaced with the IP
number of the gateway as negotiated in the IPCP.</para>
number of the gateway as negotiated by the IPCP.</para>
</listitem>
</varlistentry>
</variablelist>
@ -721,15 +735,6 @@ protocol: ppp</screen>
<filename>/usr/share/examples/ppp/ppp.conf.sample</filename> and
<filename>/usr/share/examples/ppp/ppp.linkup.sample</filename> for a
detailed example.</para>
<para>Version 2 of PPP introduces <quote>sticky routes</quote>.
Any <literal>add</literal> or <literal>delete</literal> lines
that contain <literal>MYADDR</literal> or
<literal>HISADDR</literal> will be remembered, and any time
the actual values of <literal>MYADDR</literal> or
<literal>HISADDR</literal> change, the routes will be
reapplied. This removes the necessity of repeating these
lines in <filename>ppp.linkup</filename>.</para>
</sect4>
<sect4>