我在这里按照这些说明构建了一个 3 节点 Docker Swarm 集群。
一开始我打开了多个端口,ufw
以便在 docker 节点之间进行通信:
# ufw status verbose
Status: active
Logging: on (low)
Default: deny (incoming), allow (outgoing), deny (routed)
New profiles: skip
To Action From
-- ------ ----
22/tcp ALLOW IN Anywhere
2376/tcp ALLOW IN Anywhere
2377/tcp ALLOW IN Anywhere
7946/tcp ALLOW IN Anywhere
7946/udp ALLOW IN Anywhere
4789/udp ALLOW IN Anywhere
22/tcp (v6) ALLOW IN Anywhere (v6)
2376/tcp (v6) ALLOW IN Anywhere (v6)
2377/tcp (v6) ALLOW IN Anywhere (v6)
7946/tcp (v6) ALLOW IN Anywhere (v6)
7946/udp (v6) ALLOW IN Anywhere (v6)
4789/udp (v6) ALLOW IN Anywhere (v6)
如您所见,端口 80未打开。
所以,在教程的最后,我将官方的 nginx docker 镜像部署到了集群中:
docker service create -p 80:80 --name webserver nginx
我能够输入我的服务器的 IP 地址并看到 nginx hello world 页面。
现在我想知道,为什么即使端口 80 没有打开,我也可以访问网络服务器?