[SOLVED] iptables help, don't think my changes saved
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When you do 'iptables-save' you must actually 'save' the output to your firewall script.
From the commands you did above, you did:
1) add the new rule
2) iptables-save to the screen (stdout)
3) iptables -L (which shows you the loaded iptables)
4) more iptables (this would show you a file called "iptables" if one exists in your current working directory)
I believe you should have (at step 2) dumped "iptables-save" into your firewall script, like:
shell# iptables-save > iptables
assuming your firewall script is named "iptables".
Once you add the line, the rule is implemented immediately. You don't need to restart iptables, as it's already 'kicked in'.
I'm not sure why the "-m tcp" appeared if you did not put it there, but maybe where you used "-p tcp" implies "-m tcp" automatically. Kinda makes sense-- if you want to match to TCP protocol (-p tcp), then -m is sort of implied. You'd need to check the man page or other docs to verify that this is precisely what's happening though.
For the record, here's a chunk of the iptables man page:
iptables can use extended packet matching modules. These are loaded in two ways: implicitly, when -p or --protocol
is specified, or with the -m or --match options, followed by the matching module name; after these, various extra
command line options become available, depending on the specific module. You can specify multiple extended match
modules in one line, and you can use the -h or --help options after the module has been specified to receive help
specific to that module.
So the bold part does explain why the -m showed up: it was implied by -p