shorewall_code/STABLE/documentation/starting_and_stopping_shorewall.htm

183 lines
11 KiB
HTML
Raw Normal View History

<html>
<head>
<meta http-equiv="Content-Language" content="en-us">
<meta name="GENERATOR" content="Microsoft FrontPage 5.0">
<meta name="ProgId" content="FrontPage.Editor.Document">
<meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
<title>Starting and Stopping Shorewall</title>
</head>
<body>
<table border="0" cellpadding="0" cellspacing="0" style="border-collapse: collapse" bordercolor="#111111" width="100%" id="AutoNumber1" bgcolor="#400169" height="90">
<tr>
<td width="100%">
<h1 align="center"><font color="#FFFFFF">Starting/Stopping and Monitoring the Firewall</font></h1>
</td>
</tr>
</table>
<p>
If you have a permanent internet connection such as DSL or Cable, I
recommend that you start the firewall automatically at boot. Once you
have installed "firewall" in your init.d directory, simply type "chkconfig
--add firewall". This will start the firewall in run levels 2-5 and stop
it in run levels 1 and 6. If you want to configure your firewall differently
from this default, you can use the "--level" option in chkconfig
(see "man chkconfig") or using your favorite graphical run-level editor.</p>
<p><strong><u>
<font color="#000099">
Important Note:</font></u> </strong></p>
<p>
If you use dialup, you may want to start the firewall in your /etc/ppp/ip-up.local
script. I recommend just placing "shorewall restart" in that script.
</p>
<p>
You can manually start and stop Shoreline Firewall using the "shorewall"
shell program: </p>
<ul>
<li>shorewall start - starts the firewall</li>
<li>shorewall stop - stops the firewall</li>
<li>shorewall restart - stops the firewall (if it's running) and
then starts it again</li>
<li>shorewall reset - reset the packet and byte counters in the
firewall</li>
<li>shorewall clear - remove all rules and chains installed by
Shoreline Firewall</li>
<li>shorewall refresh - refresh the rules involving the broadcast addresses
of firewall interfaces and the black and white lists.</li>
</ul>
<p>
The "shorewall" program may also be used to monitor the firewall.</p>
<ul>
<li>shorewall status - produce a verbose report about the firewall
(iptables -L -n -v)</li>
<li>shorewall show <i>chain</i> - produce a verbose report about <i>chain
</i>(iptables -L <i>chain</i> -n -v)</li>
<li>shorewall show nat - produce a verbose report about the nat table
(iptables -t nat -L -n -v)</li>
<li>shorewall show tos - produce a verbose report about the mangle table
(iptables -t mangle -L -n -v)</li>
<li>shorewall show log - display the last 20 packet log entries.</li>
<li>shorewall show connections - displays the IP connections currently being
tracked by the firewall.</li>
<li>shorewall
show
tc
- displays information about the traffic control/shaping configuration.</li>
<li>shorewall monitor [ delay ] - Continuously display the firewall
status, last 20 log entries and nat. When the log entry display
changes, an audible alarm is sounded.</li>
<li>shorewall hits - Produces several reports about the Shorewall packet log
messages in the current /var/log/messages file.</li>
<li>shorewall version - Displays the installed
version number.</li>
<li>shorewall check - Performs a <u>cursory</u> validation
of the zones, interfaces, hosts, rules and policy files.
<font size="4" color="#FF6666"><b>The &quot;check&quot; command does not parse and
validate the generated iptables commands so even though the &quot;check&quot; command
completes successfully, the configuration may fail to start. See the
recommended way to make configuration changes described below. </b></font>
</li>
<li>shorewall try<i> configuration-directory</i> [<i> timeout</i> ] - Restart shorewall using the
specified configuration and if an error occurs or if the<i> timeout </i>
option is given and the new configuration has been up for that many seconds
then shorewall is restarted using the standard configuration.</li>
<li>shorewall deny, shorewall reject, shorewall accept and shorewall save
implement <a href="blacklisting_support.htm">dynamic blacklisting</a>.</li>
<li>shorewall logwatch (added in version 1.3.2) - Monitors the
<a href="#Conf">LOGFILE </a>and produces an audible alarm when new Shorewall
messages are logged.</li>
</ul>
<p>
The <b>shorewall start</b>, <b>shorewall restart, shorewall check </b>&nbsp;and
<b>shorewall try </b>commands allow you to specify which <a href="#Configs">
Shorewall configuration</a>
to use:</p>
<blockquote>
<p>
shorewall [ -c <i>configuration-directory</i> ] {start|restart|check}<br>
shorewall try <i>configuration-directory</i></p>
</blockquote>
<p>
If a <i>configuration-directory</i> is specified, each time that Shorewall
is going to use a file in /etc/shorewall it will first look in the <i>configuration-directory</i>
. If the file is present in the <i>configuration-directory</i>, that file
will be used; otherwise, the file in /etc/shorewall will be used.</p>
<p>
When changing the configuration of a production firewall, I recommend the
following:</p>
<ul>
<li>mkdir /etc/test</li>
<li>cd /etc/test</li>
<li>&lt;copy any files that you need to change from /etc/shorewall to . and change them here&gt;</li>
<li>shorewall -c . check</li>
<li>&lt;correct any errors found by check and check again&gt;</li>
<li>/sbin/shorewall try .</li>
</ul>
<p>
If the configuration starts but doesn't work, just &quot;shorewall restart&quot; to
restore the old configuration. If the new configuration fails to start, the
&quot;try&quot; command will automatically start the old one for you.</p>
<p>
When the new configuration works then just </p>
<ul>
<li>cp * /etc/shorewall</li>
<li>cd</li>
<li>rm -rf /etc/test</li>
</ul>
<p><font size="2">
Updated 8/8/2002 - <a href="support.htm">Tom
Eastep</a>
</font></p>
<p><font face="Trebuchet MS"><a href="copyright.htm"><font size="2">Copyright</font>
<20> <font size="2">2001, 2002 Thomas M. Eastep.</font></a></font></p>
</body>
</html>