我按照说明在 Windows 10 上的 Hyper-V 中的 Ubuntu 18.04 上的 Docker 容器中设置了 Oracle 数据库这里。
但是当我使用以下命令运行容器时：
sudo docker run -d -it --rm --name oracle12se -v /home/oracle/oradata12:/opt/oracle/oradata -p 1522:1521 -p 5502:5500 -m 4G oracle/database-se:12.2.0.1
我无法从另一台 Hyper-V 机器连接到我的 Oracle 数据库，如果我使用以下命令检查连接telnet（172.17.66.84 是运行 Docker 的主机的 IP 地址）：
telnet 172.17.66.84 1522
它没有连接。但如果我检查端口 22 (SSH)：
telnet 172.17.66.84 22
连接成功，说明主机可以访问，并且IP地址正确。
要检查 Oracle 实例是否已启动，我运行
telnet 172.17.66.84 1522
或者
telnet localhost 1522
在主机上（运行 Docker 的地方）并且连接成功。
因此 IP 地址是正确的并且可以访问，Oracle 实例已运行并正在监听端口 1522，但我无法从本地网络连接到它。
更有趣的是，之前一切都运行正常，但我不知道到底发生了哪些改变。
什么可以阻止连接？
编辑1：
如果我运行一个在主机上监听 8080 端口的测试脚本，我就能够从另一台机器使用 telnet 进行连接：
telnet 172.17.66.84 8080
所以它不是 Hyper-V 或防火墙，但看起来它与 Docker 有关。
在主机上：
sudo iptables -L -n
Chain INPUT (policy ACCEPT)
target prot opt source destination
Chain FORWARD (policy ACCEPT)
target prot opt source destination
DOCKER-USER all -- 0.0.0.0/0 0.0.0.0/0
DOCKER-ISOLATION-STAGE-1 all -- 0.0.0.0/0 0.0.0.0/0
ACCEPT all -- 0.0.0.0/0 0.0.0.0/0 ctstate RELATED,ESTABLISHED
DOCKER all -- 0.0.0.0/0 0.0.0.0/0
ACCEPT all -- 0.0.0.0/0 0.0.0.0/0
ACCEPT all -- 0.0.0.0/0 0.0.0.0/0
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
Chain DOCKER (1 references)
target prot opt source destination
ACCEPT tcp -- 0.0.0.0/0 172.17.0.2 tcp dpt:5500
ACCEPT tcp -- 0.0.0.0/0 172.17.0.2 tcp dpt:1521
Chain DOCKER-ISOLATION-STAGE-1 (1 references)
target prot opt source destination
DOCKER-ISOLATION-STAGE-2 all -- 0.0.0.0/0 0.0.0.0/0
RETURN all -- 0.0.0.0/0 0.0.0.0/0
Chain DOCKER-ISOLATION-STAGE-2 (1 references)
target prot opt source destination
DROP all -- 0.0.0.0/0 0.0.0.0/0
RETURN all -- 0.0.0.0/0 0.0.0.0/0
Chain DOCKER-USER (1 references)
target prot opt source destination
RETURN all -- 0.0.0.0/0 0.0.0.0/0
ifconfig
docker0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.17.0.1 netmask 255.255.0.0 broadcast 172.17.255.255
inet6 fe80::42:98ff:feb3:fbe8 prefixlen 64 scopeid 0x20<link>
ether 02:42:98:b3:fb:e8 txqueuelen 0 (Ethernet)
RX packets 88 bytes 2768 (2.7 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 123 bytes 10688 (10.6 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.17.66.84 netmask 255.255.255.240 broadcast 172.17.66.95
inet6 fe80::980a:fe52:5a8d:1bb7 prefixlen 64 scopeid 0x20<link>
ether 00:15:5d:08:73:28 txqueuelen 1000 (Ethernet)
RX packets 451608 bytes 655072327 (655.0 MB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 101353 bytes 8256682 (8.2 MB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Local Loopback)
RX packets 2853 bytes 157368 (157.3 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 2853 bytes 157368 (157.3 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
vethbab7679: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::942e:fff:feee:b333 prefixlen 64 scopeid 0x20<link>
ether 96:2e:0f:ee:b3:33 txqueuelen 0 (Ethernet)
RX packets 88 bytes 4000 (4.0 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 166 bytes 15352 (15.3 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
编辑2：
sudo iptables -t nat -L -n
Chain PREROUTING (policy ACCEPT)
target prot opt source destination
DOCKER all -- 0.0.0.0/0 0.0.0.0/0 ADDRTYPE match dst-type LOCAL
Chain INPUT (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
DOCKER all -- 0.0.0.0/0 !127.0.0.0/8 ADDRTYPE match dst-type LOCAL
Chain POSTROUTING (policy ACCEPT)
target prot opt source destination
MASQUERADE all -- 172.17.0.0/16 0.0.0.0/0
MASQUERADE tcp -- 172.17.0.2 172.17.0.2 tcp dpt:5500
MASQUERADE tcp -- 172.17.0.2 172.17.0.2 tcp dpt:1521
Chain DOCKER (2 references)
target prot opt source destination
RETURN all -- 0.0.0.0/0 0.0.0.0/0
DNAT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:5502 to:172.17.0.2:5500
DNAT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:1522 to:172.17.0.2:1521
sudo docker info
Containers: 1
Running: 1
Paused: 0
Stopped: 0
Images: 57
Server Version: 18.09.5
Storage Driver: overlay2
Backing Filesystem: extfs
Supports d_type: true
Native Overlay Diff: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: bridge host macvlan null overlay
Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: bb71b10fd8f58240ca47fbb579b9d1028eea7c84
runc version: 2b18fe1d885ee5083ef9f0838fee39b62d653e30
init version: fec3683
Security Options:
apparmor
seccomp
Profile: default
Kernel Version: 4.15.0-48-generic
Operating System: Ubuntu 18.04.2 LTS
OSType: linux
Architecture: x86_64
CPUs: 2
Total Memory: 9.758GiB
Name: tor
ID: TN5P:KKCD:TGRU:HQHV:6SH7:6WTJ:U445:6WYC:D7LS:D6AW:BFVC:2B2U
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): false
Registry: https://index.docker.io/v1/
Labels:
Experimental: false
Insecure Registries:
127.0.0.0/8
Live Restore Enabled: false
Product License: Community Engine
WARNING: No swap limit support