在iptables规则中添加FTP端口时出错

我想添加FTP端口在我的iptableconfiguration，我怀疑我无法通过FileZilla访问我的FTP的原因。

/etc/iptables.firewall.rules

*filter # Allow all loopback (lo0) traffic and drop all traffic to 127/8 that doesn't use lo0 -A INPUT -i lo -j ACCEPT -A INPUT -d 127.0.0.0/8 -j REJECT # Accept all established inbound connections -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT # Allow all outbound traffic - you can modify this to only allow certain traffic -A OUTPUT -j ACCEPT # Allow HTTP and HTTPS connections from anywhere (the normal ports for websites and SSL). -A INPUT -p tcp --dport 80 -j ACCEPT -A INPUT -p tcp --dport 443 -j ACCEPT # Allow SSH connections # # The -dport number should be the same port number you set in sshd_config # -A INPUT -p tcp -m state --state NEW --dport 22 -j ACCEPT # Just added for FTP -A INPUT -p tcp -m tcp --dport 21 -m conntrack --ctstate ESTABLISHED -j ACCEPT -m comment --comment "Allow ftp connections on port 21" -A OUTPUT -p tcp -m --dport 21 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT -m comment --comment "Allow ftp connections on port 21" -A INPUT -p tcp -m tcp --dport 20 -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT -m comment --comment "Allow ftp connections on port 20" -A OUTPUT -p tcp --dport 20 -m conntrack --ctstate ESTABLISHED -j ACCEPT -m comment --comment "Allow ftp connections on port 20" # Allow ping -A INPUT -p icmp -j ACCEPT # Log iptables denied calls -A INPUT -m limit --limit 5/min -j LOG --log-prefix "iptables denied: " --log-level 7 # Drop all other inbound - default deny unless explicitly allowed policy -A INPUT -j DROP -A FORWARD -j DROP COMMIT 

我添加的唯一的东西是脚本下面的评论# Just added for FTP

现在，当我尝试使用它来加载它时， iptables-restore < /etc/iptables.firewall.rules出现这样的错误：

 iptables-restore v1.4.12: Couldn't load match `--dport':No such file or directory Error occurred at line: 25 

我不是这方面的专家，这是我个人用于随机练习的VPS盒子。

什么似乎是原因？

 -m --dport 

 -m tcp --dport