[伊達隨筆]iptables解決FTP登錄慢的問題

iptables -t filter -A INPUT -p tcp --dport 22 -j ACCEPT  
iptables -t filter -A INPUT -p tcp --dport 20:21 -m state --state NEW,ESTABLISHED -j ACCEPT  
iptables -t filter -A INPUT -p tcp --sport 20:21 -m state --state NEW,ESTABLISHED -j ACCEPT  
iptables -t filter -A OUTPUT -p tcp --dport 20:21 -m state --state ESTABLISHED -j ACCEPT  
iptables -t filter -A OUTPUT -p tcp --sport 20:21 -m state --state ESTABLISHED -j ACCEPT  
iptables -I INPUT -p udp --sport 53 -j ACCEPT
iptables -I INPUT -p tcp --sport 53 -j ACCEPT
iptables -t filter -P INPUT DROP

[root@jyoe ~]# iptables -L
Chain INPUT (policy DROP)
target     prot opt source               destination        
ACCEPT     tcp  --  anywhere             anywhere            tcp spt:domain
ACCEPT     udp  --  anywhere             anywhere            udp spt:domain
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:ssh
ACCEPT     tcp  --  anywhere             anywhere            tcp dpts:ftp-data:ftp state NEW,ESTABLISHED
ACCEPT     tcp  --  anywhere             anywhere            tcp spts:ftp-data:ftp state NEW,ESTABLISHED

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination        

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination        
ACCEPT     tcp  --  anywhere             anywhere            tcp dpts:ftp-data:ftp state ESTABLISHED
ACCEPT     tcp  --  anywhere             anywhere            tcp spts:ftp-data:ftp state ESTABLISHED