在7-6中，生成到node-3的dubbo服务正常，在node-1的ZK也能注册，dubbo服务也能测试。

[root@node-1 configs]# cat dubbo.yaml
      hostNetwork: true
      nodeName: node-3
        ports:
        - containerPort: 20881
        env:
        - name: DUBBO_PORT
          value: "20881"

[root@node-1 configs]# kubectl get pods -o wide
NAME                           READY   STATUS    RESTARTS   AGE    IP               NODE     NOMINATED NODE   READINESS GATES
dubbo-demo-5fb89b885d-lwv2l    1/1     Running   0          3s     172.16.1.23 

[root@node-3 harbor]# crictl ps
CONTAINER           IMAGE               CREATED             STATE               NAME                   ATTEMPT             POD ID
7ba8f3af36475       a5878a1e012c5       7 seconds ago       Running             dubbo-demo             0                   85d4ecd045c17
#查看部署节点端口
[root@node-3 harbor]# netstat -lntup|grep 20881
tcp        0      0 0.0.0.0:20881           0.0.0.0:*               LISTEN      92021/java 

#测试dubbo
[root@node-2 ~]# telnet 172.16.1.23 20881
Trying 172.16.1.23...
Connected to 172.16.1.23.
Escape character is '^]'.
dubbo>ls
com.mooc.demo.api.DemoService
dubbo>ls com.mooc.demo.api.DemoService
sayHello
dubbo>invoke com.mooc.demo.api.DemoService.sayHello("xxx")
"Hello xxx"
elapsed: 4 ms.
dubbo>exit
Connection closed by foreign host.

[root@node-1 zookeeper]# docker run --name zookeeper -p 2181:2181 --restart always -d hub.mooc.com/zookeeper/zookeeper:3.4.10

此时，我要通过7-7的web项目调取7-6的服务失败。
执行操作如下:

[root@node-1 web-demo]# cat start.sh
#!/bin/bash
sh /usr/local/tomcat/bin/startup.sh
tail -f /usr/local/tomcat/logs/catalina.out
[root@node-1 web-demo]# chmod +x start.sh
[root@node-1 web-demo]# ll start.sh 
-rwxr-xr-x 1 root root 92 Nov 12 05:33 start.sh


[root@node-1 web-demo]# cat Dockerfile
FROM hub.mooc.com/kubernetes/tomcat:8.0.51-alpine

COPY ROOT /usr/local/tomcat/webapps/ROOT

COPY start.sh /usr/local/tomcat/bin/start.sh

ENTRYPOINT ["sh" , "/usr/local/tomcat/bin/start.sh"]

[root@node-1 web-demo]# docker build -t web:v1 .

[root@node-1 web-demo]# docker run -it web:v1

执行上述docker run抛出的异常结果:

[2022-11-11 22:50:49.814] {ERROR} com.alibaba.dubbo.registry.zookeeper.ZookeeperRegistry 146 -  
[DUBBO] Failed to register consumer://172.17.0.3/com.mooc.demo.api.DemoService?application=demo&category=consumers&check=false&default.retries=3&default.timeout=60000&dubbo=2.6.2&interface=com.mooc.demo.api.DemoService&methods=sayHello&pid=14&revision=1.0-SNAPSHOT&side=consumer&timestamp=1668207005427, waiting for retry, cause: 
Failed to register consumer://172.17.0.3/com.mooc.demo.api.DemoService?application=demo&category=consumers&check=false&default.retries=3&default.timeout=60000&dubbo=2.6.2&interface=com.mooc.demo.api.DemoService&methods=sayHello&pid=14&revision=1.0-SNAPSHOT&side=consumer&timestamp=1668207005427 to zookeeper 
zookeeper://172.16.1.23:2181/com.alibaba.dubbo.registry.RegistryService?application=demo&dubbo=2.6.2&interface=com.alibaba.dubbo.registry.RegistryService&pid=14&timestamp=1668207005494, cause: KeeperErrorCode = ConnectionLoss, dubbo version: 2.6.2, 
current host: 172.17.0.3
com.alibaba.dubbo.rpc.RpcException: Failed to register 
consumer://172.17.0.3/com.mooc.demo.api.DemoService?application=demo&category=consumers&check=false&default.retries=3&default.timeout=60000&dubbo=2.6.2&interface=com.mooc.demo.api.DemoService&methods=sayHello&pid=14&revision=1.0-SNAPSHOT&side=consumer&timestamp=1668207005427 to zookeeper 
zookeeper://172.16.1.23:2181/com.alibaba.dubbo.registry.RegistryService?application=demo&dubbo=2.6.2&interface=com.alibaba.dubbo.registry.RegistryService&pid=14&timestamp=1668207005494, cause: KeeperErrorCode = ConnectionLoss

node-1的IP为172.16.1.21
node-3的IP为172.16.1.23
是互通的。

但是在tomcat内部运行的话，我如何连接到docker运行的ZK服务，并让7-7的web服务能调通7-6的dubbo服务？
我发现日志中的172.17.0.3是进入tomcat的bash环境读取来的。

[root@node-1 zookeeper]# docker run -it --entrypoint bash hub.mooc.com/kubernetes/tomcat:8.0.51-alpine
bash-4.4# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
57: eth0@if58: <BROADCAST,MULTICAST,UP,LOWER_UP,M-DOWN> mtu 1500 qdisc noqueue state UP 
    link/ether 02:42:ac:11:00:03 brd ff:ff:ff:ff:ff:ff
    inet 172.17.0.3/16 brd 172.17.255.255 scope global eth0
       valid_lft forever preferred_lft forever