How to write an IPtables script

[nick1]

Greetings,

I'm running Ubuntu 6.06LTS Server (command-line based, no GUI) and wish to configure IPtables. I have my script written and saved in a text file. At this point, I'm confused about several things. I've searched google and unfortunately have not found a clear explanation to my questions.

1.) How do I automatically execute the script at bootup?
--Do I need to change the file extension of the text file?
--Do I have to add "#!/bin/bash" to the top of the script?
--Where do I place the script, in the /etc/init.d directory?
--What permissions does the script need to run at bootup?

2.) Some IPtables scripts I've come across include the following:

modprobe ip_tables
modprobe ip_conntrack_ftp

My Ubuntu server is not providing FTP, just HTTP and SSH, so do I need to include these lines of code in my IPtables script?

Thank you for your time,

*Nick*

[maclinwin]

Most apps configure a boot script. The last time I manually did one was on Mandrake 8 by editing:

/etc/init.d/rc.d

It was commented as to where/how to add the start up commands. I only mention this to stir some more expert comment.

Execute an:

cat /etc/init.d to view it contents. To edit replace "cat" with "vi". If your confused, don't bother as your wasting your time.

In *nix file extensions are not important. Check the permission on your file.

execute an "ls -las" on any directory to list details of file attributes. they will look like "rwx". The x bit is critical for execution.

If your this new, don't bother with IP tables. Just get a router from your local store. It is cheap and removes a tedious detail from your server.

Don't be afraid to view the "man" pages. Great advice for anyone new to Unix.

"man mystery command.