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From: Jacob Friis Larsen <jfl@list.idg.dk>
To: Aleksandar Milivojevic <amilivojevic@pbl.ca>
Cc: netfilter@lists.netfilter.org
Subject: Re: Port is open but I am unable to connect
Date: Wed, 08 Sep 2004 08:47:18 +0200	[thread overview]
Message-ID: <413EAAF6.5030804@list.idg.dk> (raw)
In-Reply-To: <413E2123.6050908@pbl.ca>

 > All your rules (apart from lo interface) are for INPUT chain. No rules
 > for OUTPUT chain (so all return packets get dropped there).  You are
 > missing "-A OUTPUT -m state --state ESTABLISHED,RELATED -j ACCEPT" at
 > the begining of your rules (just after similar INPUT line you already
 > have).

Sounds logic. I changed it in the script below, and will try it out 
later when I can get to the server.

 > BTW, what's the point of accepting connections to port 20? It's FTP
 > port used for active data transfers, and connections are made *from*
 > it, not *to* it.  Since you have (will have) "just accept anything
 > related I don't care" rules, just add "modprobe ip_nat_ftp" line
 > somewhere into your script, and FTP will work (you don't need that
 > port 20 line).

OK, I changed that too.

Thanks a lot!
Jacob

>> This is my script:
> 
> [snip]
> 
modprobe ip_nat_ftp

>> # STATE RELATED for router
>> iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A OUTPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
>>
>> # Localhost
>> iptables -A INPUT -i lo -j ACCEPT
>> iptables -A OUTPUT -o lo -j ACCEPT
>>
>> # Open ports on router for server/services
#iptables -A INPUT -s 1.2.3.4 -j ACCEPT -p tcp --dport 20 -m state
>> --state NEW
>> iptables -A INPUT -s 1.2.3.4 -j ACCEPT -p tcp --dport 21 -m state 
>> --state NEW
>> iptables -A INPUT -s 1.2.3.4 -j ACCEPT -p tcp --dport 22 -m state 
>> --state NEW
>> iptables -A INPUT -j ACCEPT -p tcp --dport 25 -m state --state NEW
>> iptables -A INPUT -j ACCEPT -p tcp --dport 80 -m state --state NEW
>> iptables -A INPUT -j ACCEPT -p tcp --dport 143 -m state --state NEW
>> iptables -A INPUT -j ACCEPT -p tcp --dport 993 -m state --state NEW


  reply	other threads:[~2004-09-08  6:47 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-09-07 19:27 Port is open but I am unable to connect Jacob Friis Larsen
2004-09-07 19:35 ` Sascha Reissner
2004-09-08  6:34   ` Jacob Friis Larsen
2004-09-07 20:19 ` Jason Opperisano
2004-09-08  6:38   ` Jacob Friis Larsen
2004-09-08 11:35     ` Jason Opperisano
2004-09-07 20:59 ` Aleksandar Milivojevic
2004-09-08  6:47   ` Jacob Friis Larsen [this message]
2004-09-09 10:17     ` Jacob Friis Larsen
2004-09-09 12:20       ` Jason Opperisano

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