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Old 05-02-2001, 06:47 PM   #1
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Registered: Apr 2001
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I have Redhat for dummies.... I.E. Me..
I want to create a firewall, and in the book that came with my redhat, it just makes statements that I don't understand.

It says... "Create a script called, "ipfilter.eth0" in the /usr/local/etc directory" ???????? HOW.....
and also.. do I type the symbol "#" when I type the lines???

any help would be great.. thanks
Old 05-03-2001, 04:56 AM   #2
Registered: Apr 2001
Location: London
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Like DOS you can create batch files in Linux called scripts.
But due to the permissions you have to tell the file its an executable.

to create and empty script file in Linux type this:
# (this is the prompt you should have when your root)
$ su - root
# echo '#!/bin/sh' > /usr/local/etc/ipfilter.eth0

this has made the start of a shell script in the directory you said.

now you have to tell the system you want it executable.

# chmod 700 /usr/local/etc/ipfilter.eth0

Now you just have to learn how to write shell scripts and run the file with your program in it.

Old 01-04-2002, 08:46 AM   #3
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Question Here's what I didn't understand...

This is what I did, not sure what to make of it:

1) Copied the files ipfilter.rules and ipfilter.release from CD3 into the /usr/local/etc/ directory

2) Did a search and replace for ppp0 to eth0 on ipfilter.rules

3) Saved ipfilter.rules as ipfilter.eth0

4) Did a chmod 770 /usr/local/etc/ipfilter.*

5) Tried to execute the ipfilter.eth0 file, with no joy. Tried again, rinse, lather, repeat, no joy.

6) Read this post

7) Deleted both files, and did the "# echo '#!/bin/sh' > /usr/local/etc/ipfilter.eth0" command, which created the new ipfilter.eth0 file

8) Opened the file from the CD, copied the contents, and pasted it into the new ipfilter.eth0 file. Searched, Replaced, Saved. Did the same steps to create and past into the ipfilter.release.

9) Did the same chmod command, chmod 770 /usr/local/etc/ipfilter.*

10) They executed and worked as designed

Here's my question... why did the file(s) on the CD not execute after the chmod, but when I first created the file locally then pasted the same contents, it worked w/o a problem?

Thanks! Newbie here
Old 01-04-2002, 08:58 AM   #4
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As far as I can see the second time you added the first line, which said '#!/bin/sh'. This line the shell which program should run the script. If you don't include that file it won't run unless you specifically tell it to run with that program. Like 'sh scriptfile'.
Old 01-04-2002, 09:46 AM   #5
Registered: Oct 2001
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well, you don't HAVE to specify the shell to run it in. if you don't include #!/bin/sh then it'll just drop the commands to the chell you are currently using, e.g. bash or sh. you have to specify perl or awk tho, as those commands mean nothign to sh
Old 01-08-2002, 10:22 AM   #6
Registered: Dec 2001
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Thanks, you saved my day!

I had the same problem, a script that just would not run.

Your post was really helpful, thanks!!!

Keep up the great spirit, Linux is getting into my heart more and more!!! ;-)




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