Redirect Ubuntu上的KVM：端口转发到来宾VM

我安装了kvm，并使用vmbuilder在服务器上设置了几个来宾。以下是以下配置：

server host1 (xxx.xxx.xxx.xxx) ->  guest vm1 (192.168.122.203)
                               ->  guest vm2 (192.168.122.204)

其中xxx.xxx.xxx.xxx是主机1的固定IP地址

我想使用以下命令连接到vm1：

ssh username@host1 -p 2222

我尝试在iptables中添加以下规则：

sudo iptables --table nat --append PREROUTING --protocol tcp --destination xxx.xxx.xxx.xxx --destination-port 2222 --jump DNAT --to-destination 192.168.122.203:22

但我在跑步时超时了：

ssh username@host1 -p 2222

以下是我的iptables规则：

sudo iptables -nL -v --line-numbers -t nat
Chain PREROUTING (policy ACCEPT 32446 packets, 3695K bytes)
num   pkts bytes target     prot opt in     out     source               destination         
1        7   420 DNAT       tcp  --  *      *       0.0.0.0/0            xxx.xxx.xxx.xxx        tcp dpt:2222 to:192.168.122.203:22

Chain INPUT (policy ACCEPT 8961 packets, 968K bytes)
num   pkts bytes target     prot opt in     out     source               destination         

Chain OUTPUT (policy ACCEPT 350 packets, 23485 bytes)
num   pkts bytes target     prot opt in     out     source               destination         

Chain POSTROUTING (policy ACCEPT 357 packets, 23905 bytes)
num   pkts bytes target     prot opt in     out     source               destination         
1      151  9060 MASQUERADE  tcp  --  *      *       192.168.122.0/24    !192.168.122.0/24     masq ports: 1024-65535
2       99  7524 MASQUERADE  udp  --  *      *       192.168.122.0/24    !192.168.122.0/24     masq ports: 1024-65535
3        3   252 MASQUERADE  all  --  *      *       192.168.122.0/24    !192.168.122.0/24



sudo iptables -nL -v --line-numbers 
Chain INPUT (policy ACCEPT 14 packets, 1147 bytes)
num   pkts bytes target     prot opt in     out     source               destination         
1      454 30229 ACCEPT     udp  --  virbr0 *       0.0.0.0/0            0.0.0.0/0            udp dpt:53
2        0     0 ACCEPT     tcp  --  virbr0 *       0.0.0.0/0            0.0.0.0/0            tcp dpt:53
3        0     0 ACCEPT     udp  --  virbr0 *       0.0.0.0/0            0.0.0.0/0            udp dpt:67
4        0     0 ACCEPT     tcp  --  virbr0 *       0.0.0.0/0            0.0.0.0/0            tcp dpt:67

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
num   pkts bytes target     prot opt in     out     source               destination         
1     589K 2304M ACCEPT     all  --  *      virbr0  0.0.0.0/0            192.168.122.0/24     state RELATED,ESTABLISHED
2     403K   24M ACCEPT     all  --  virbr0 *       192.168.122.0/24     0.0.0.0/0           
3        0     0 ACCEPT     all  --  virbr0 virbr0  0.0.0.0/0            0.0.0.0/0           
4        1    60 REJECT     all  --  *      virbr0  0.0.0.0/0            0.0.0.0/0            reject-with icmp-port-unreachable
5        0     0 REJECT     all  --  virbr0 *       0.0.0.0/0            0.0.0.0/0            reject-with icmp-port-unreachable

Chain OUTPUT (policy ACCEPT 4 packets, 480 bytes)
num   pkts bytes target     prot opt in     out     source               destination

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任何建议都将不胜感激。

好的，我找到了答案：

我将这两条规则添加到nat表中：

$sudo iptables -t nat -A PREROUTING -p tcp --dport 2222 -j DNAT --to-destination 192.168.122.203:22
$sudo iptables -t nat -A POSTROUTING -p tcp --dport 22 -d 192.168.122.203 -j SNAT --to 192.168.122.1

然后我删除了表过滤器前链的规则4和规则5

$sudo iptables -nL -v --line-numbers -t filter

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
(...)        
4        7   420 REJECT     all  --  *      virbr0  0.0.0.0/0            0.0.0.0/0            reject-with icmp-port-unreachable
5        0     0 REJECT     all  --  virbr0 *       0.0.0.0/0            0.0.0.0/0            reject-with icmp-port-unreachable

$sudo iptables -D FORWARD 5 -t filter
$sudo iptables -D FORWARD 4 -t filter

现在我通过以下操作连接到vm1：

$ssh user1@host -p 2222
user1@vm1:~$

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你是如何使来宾虚拟机的IP保持静态的？也许这是导致拒绝规则存在的原因？