IPTable을 통한 PPTP

저는 최근 iptables를 실행하는 네트워크에 Raspberry Pi 방화벽/게이트웨이를 구현했습니다.

구현 이후 직장에서 Windows 기반 PPTP 서버에 연결할 수 없었습니다.

나는 "모든 것을 허용한다"는 규칙이 있다고 생각했지만 그렇지 않은 것 같습니다. 전체 iptables 스크립트는 아래에 나열되어 있습니다.

PATH=/usr/sbin:/sbin:/bin:/usr/bin

iptables -F
iptables -t nat -F
iptables -t mangle -F
iptables -X

iptables -A INPUT -i lo -j ACCEPT

iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT -m state --state NEW -i eth1 -j ACCEPT
iptables -A FORWARD -i eth1 -o eth0 -m state --state ESTABLISHED,RELATED -j ACCEPT

iptables -A INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT

iptables -A FORWARD -i eth0 -o eth1 -j ACCEPT

iptables -t nat -A POSTROUTING -o eth1 -j MASQUERADE

iptables -A FORWARD -i eth1 -o eth1 -j REJECT

echo 1 > /proc/sys/net/ipv4/ip_forward

내 iptables -L -vn의 결과는 다음과 같습니다. iptables -t nat -L -vn:

Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         
    0     0 ACCEPT     all  --  lo     *       0.0.0.0/0            0.0.0.0/0           
   21  1572 ACCEPT     all  --  *      *       0.0.0.0/0            0.0.0.0/0            state RELATED,ESTABLISHED
    0     0 ACCEPT     all  --  eth1   *       0.0.0.0/0            0.0.0.0/0            state NEW
    0     0 ACCEPT     tcp  --  *      *       0.0.0.0/0            0.0.0.0/0            state NEW tcp dpt:22

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         
    9   656 ACCEPT     all  --  eth1   eth0    0.0.0.0/0            0.0.0.0/0            state RELATED,ESTABLISHED
    0     0 ACCEPT     tcp  --  eth1   eth0    0.0.0.0/0            0.0.0.0/0            tcp dpt:1723 state NEW,ESTABLISHED
    0     0 ACCEPT     tcp  --  eth0   eth1    0.0.0.0/0            0.0.0.0/0            tcp spt:1723 state RELATED,ESTABLISHED
    0     0 ACCEPT     47   --  eth1   eth1    0.0.0.0/0            0.0.0.0/0            state NEW,ESTABLISHED
    0     0 ACCEPT     47   --  eth0   eth1    0.0.0.0/0            0.0.0.0/0            state RELATED,ESTABLISHED
    9   498 ACCEPT     all  --  eth0   eth1    0.0.0.0/0            0.0.0.0/0           
    0     0 REJECT     all  --  eth1   eth1    0.0.0.0/0            0.0.0.0/0            reject-with icmp-port-unreachable

Chain OUTPUT (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         
   11  1212 ACCEPT     all  --  *      *       0.0.0.0/0            0.0.0.0/0            state NEW,ESTABLISHED
Chain PREROUTING (policy ACCEPT 1 packets, 64 bytes)
 pkts bytes target     prot opt in     out     source               destination         
    0     0 DNAT       tcp  --  eth1   *       0.0.0.0/0            0.0.0.0/0            tcp dpt:1723 to:192.168.1.51
    0     0 DNAT       47   --  eth1   *       0.0.0.0/0            0.0.0.0/0            to:192.168.1.51

Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         

Chain OUTPUT (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         

Chain POSTROUTING (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         
    1    64 MASQUERADE  all  --  *      eth1    0.0.0.0/0            0.0.0.0/0