Shorewall Support Guide
Tom
Eastep
2004-07-29
2001-2004
Thomas M. Eastep
Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License, Version
1.2 or any later version published by the Free Software Foundation; with
no Invariant Sections, with no Front-Cover, and with no Back-Cover
Texts. A copy of the license is included in the section entitled
GNU Free Documentation License
.
Before Reporting a Problem or Asking a Question
There are a number of sources of Shorewall information. Please try
these before you post.
The two currently-supported Shorewall major releases are 1.4 and 2.0.
More than half of the questions posted on the support list have
answers directly accessible from the Documentation Index
The FAQ has solutions to more than
30 common problems.
The Troubleshooting Information
contains a number of tips to help you solve common problems.
The Errata has links to download
updated components.
The Site
and Mailing List Archives search facility can locate documents
and posts about similar problems:
Problem Reporting Guidelines
Shorewall versions earlier that 1.4.0 are no longer supported.
Please remember we only know what is posted in your message. Do
not leave out any information that appears to be correct, or was
mentioned in a previous post. There have been countless posts by
people who were sure that some part of their configuration was correct
when it actually contained a small error. We tend to be skeptics where
detail is lacking.
Please keep in mind that you're asking for free technical support. Any help we offer is an
act of generosity, not an obligation. Try to make it easy for us to
help you. Follow good, courteous practices in writing and formatting
your e-mail. Provide details that we need if you expect good answers.
Exact quoting of error messages, log entries, command output, and
other output is better than a paraphrase or summary.
Please don't describe your problem as Computer A
can't see Computer B
. Of course it can't -- it
hasn't any eyes! If ping from A to B fails, say so (and see below
for information about reporting ping
problems). If
Computer B doesn't show up in Network Neighborhood
then say so.
Please give details about what doesn't work. Reports that
say I followed the directions and it didn't work
will elicit sympathy but probably little in the way of help. Again --
if ping from A to B fails, say so (and see below for information about
reporting ping
problems). If Computer B doesn't
show up in Network Neighborhood
then say so. If access
by IP address works but by DNS names it doesn't then say so.
Please don't describe your environment and then ask us to
send you custom configuration files. We're here to answer your
questions but we can't do your job for you.
Please do NOT include the output of iptables -L
— the output of shorewall show or
shorewall status is much more useful.
When reporting a problem, ALWAYS
include this information:
the exact version of Shorewall you are running.
shorewall version
the complete, exact output of
ip addr show
the complete, exact output of
ip route show
THIS IS IMPORTANT! If your
problem is that some type of connection to/from or through your
firewall isn't working then please perform the following four
steps:
If Shorewall isn't started then /sbin/shorewall/start.
Otherwise /sbin/shorewall reset.
Try making the connection that is failing.
/sbin/shorewall status > /tmp/status.txt
Post the /tmp/status.txt file as an
attachment (you may compress it if you like).
the exact wording of any ping failure responses
If you installed Shorewall using one
of the QuickStart Guides, please indicate which one.
As a general matter, please do not edit
the diagnostic information in an attempt to conceal your IP
address, netmask, nameserver addresses, domain name, etc. These
aren't secrets, and concealing them often misleads us (and 80% of
the time, a hacker could derive them anyway from information contained
in the SMTP headers of your post).
Do you see any Shorewall
messages (/sbin/shorewall
show log
) when you exercise the function that is
giving you problems? If so, include the message(s) in your post along
with a copy of your /etc/shorewall/interfaces file.
Please include any of the Shorewall configuration files
(especially the /etc/shorewall/hosts file if you have modified that
file) that you think are relevant. If you include
/etc/shorewall/rules, please include /etc/shorewall/policy as well
(rules are meaningless unless one also knows the policies).
If an error occurs when you try to shorewall
start
, include a trace (See the Troubleshooting section for
instructions).
The list server limits posts to 120kb so
don't post graphics of your network layout, etc. to the Mailing
List -- your post will be rejected.
The author gratefully acknowleges that the above list was
heavily plagiarized from the excellent LEAF document by
Ray Olszewski found at http://leaf-project.org/pub/doc/docmanager/docid_1891.html.
When using the mailing list, please post in plain text
A growing number of MTAs serving list subscribers are rejecting all
HTML traffic. At least one MTA has gone so far as to blacklist
shorewall.net for continuous abuse
because it has been my
policy to allow HTML in list posts!!
I think that blocking all HTML is a Draconian way to control spam
and that the ultimate losers here are not the spammers but the list
subscribers whose MTAs are bouncing all shorewall.net mail. As one list
subscriber wrote to me privately These e-mail admin's need to
get a (expletive deleted) life instead of trying to rid the planet of HTML
based e-mail
. Nevertheless, to allow subscribers to receive list
posts as must as possible, I have now configured the list server at
shorewall.net to convert all HTML to plain text. These converted posts are
difficult to read so all of us will appreciate it if you just post in
plain text to begin with.
Where to Send your Problem Report or to Ask for Help
If you run the current development release
(see the Shorewall Release Model page)
-- please post your question or problem to the Shorewall Development
Mailing List.
If you run Shorewall under MandrakeSoft Multi
Network Firewall (MNF) and you have not purchased an MNF license from
MandrakeSoft then you can post non MNF-specific Shorewall questions to the
Shorewall users
mailing list. Do not expect to get free MNF support on the list.
Otherwise, please post your question or problem to the Shorewall users mailing
list. IMPORTANT: If you are not
subscribed to the list, please say so -- otherwise, you will not be
included in any replies.
Subscribing to the Users Mailing List
To Subscribe to the mailing list go to https://lists.shorewall.net/mailman/listinfo/shorewall-users.
Other Mailing Lists
For information on other Shorewall mailing lists, go to http://lists.shorewall.net .
Revision History
1.62003-07-03TENew
Release Model1.52003-05-16TEAdd
link to the troubleshooting section1.42003-03-15TERemove
Newbies Mailing List.1.32003-02-19TEAdmonish
against including "iptables -L" output.1.22003-01-01TERemoved
.GIF and moved note about unsupported releases. Move Revision History to
this Appendix.1.12003-12-19TECorrected
URL for Newbies List