docker - docker 19.03 上的用户定义网络与 CentOS 8 不工作

Question

环境设置：

OS: CentOS Linux release 8.2.2004 (Core)
Docker Version: 
 Client: Docker Engine - Community
    Version:           19.03.11
    API version:       1.40
    Go version:        go1.13.10
    Git commit:        42e35e61f3
    Built:             Mon Jun  1 09:13:48 2020
    OS/Arch:           linux/amd64
    Experimental:      false

  Server: Docker Engine - Community
    Engine:
      Version:          19.03.11
      API version:      1.40 (minimum version 1.12)
      Go version:       go1.13.10
      Git commit:       42e35e61f3
      Built:            Mon Jun  1 09:12:26 2020
      OS/Arch:          linux/amd64
      Experimental:     false
      containerd:
         Version:          1.2.6
         GitCommit:        894b81a4b802e4eb2a91d1ce216b8817763c29fb
      runc:
         Version:          1.0.0-rc8
         GitCommit:        425e105d5a03fabd737a126ad93d62a9eeede87f
      docker-init:
         Version:          0.18.0
         GitCommit:        fec3683

Linux 机器连接到防火墙后面的公司网络。以下是详细信息：

1. /etc/hosts

     127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
     ::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
   

2. /etc/resolv.conf

     # Generated by NetworkManager
       search subdomain.domain.com
       nameserver 13.108.0.11
       nameserver 13.108.11.16
   

3. 创建用户定义的桥接网络：

    $ docker network create mynetwork
    $ docker network ls
    NETWORK ID          NAME                DRIVER              SCOPE
    05400c341d1d        bridge              bridge              local
    fb4e364ad31b        host                host                local
    835f9d99e610        none                null                local
    7d8fc26d3632        mynetwork           bridge              local
   

4. 在 mynetwork 上创建了两个容器：

   $ docker container run --name search1 --network mynetwork --network-alias search --detach elasticsearch:2
   

   和

   $ docker container run --name search2 --network mynetwork --network-alias search --detach elasticsearch:2
   

5. DNS 循环检查：

   $ docker container run --rm -it --network mynetowrk alpine nslookup search

   输出：

    Server:         127.0.0.11
    Address:        127.0.0.11:53
    ** server can't find search.subdomain.domain.com: NXDOMAIN
    ** server can't find search.subdomain.domain.com: NXDOMAIN
   

6. 容器 /etc/resolv.conf

    $ docker container run --rm -it --network mynetwork alpine cat /etc/resolv.conf
   

   输出：

    search subdomain.domain.com
    nameserver 127.0.0.11
    options ndots:0
   

7. Docker 用户定义的网络详细信息：

   $ docker network inspect -v mynetwork

输出：

     [
         {
             "Name": "mynetwork",
             "Id": "7d8fc26d36323cf9ba47dbb272bf4ad15113d6b26a26fbf6c82cc1d866b480c0",
             "Created": "2020-06-18T09:54:12.37673638+05:30",
             "Scope": "local",
             "Driver": "bridge",
             "EnableIPv6": false,
             "IPAM": {
                 "Driver": "default",
                 "Options": {},
                 "Config": [
                     {
                         "Subnet": "172.19.0.0/16",
                         "Gateway": "172.19.0.1"
                     }
                 ]
             },
             "Internal": false,
             "Attachable": true,
             "Ingress": false,
             "ConfigFrom": {
                 "Network": ""
             },
             "ConfigOnly": false,
             "Containers": {
             "ec1cacb437926b5c6bb5693ab9c0afa6f8bc2764d5e15a5e15d9d5709346c1e5": {
                     "Name": "search1",
                     "EndpointID": "2c7420176adbce496e4c033416d98c290cf74dcc1e68568d7160b45cefd8d1db",
                     "MacAddress": "02:42:ac:13:00:02",
                     "IPv4Address": "172.19.0.2/16",
                     "IPv6Address": ""
                 },
            "f7cf532aa71df9cefaf5575ff27d4a2f4525f7674a479989d5b96f281282b6db": {
                     "Name": "search2",
                     "EndpointID": "d641f94dfc1d898d7d8ec667b4389d4ff6a0d53be3454a89f77b24b0bd04a663",
                     "MacAddress": "02:42:ac:13:00:03",
                     "IPv4Address": "172.19.0.3/16",
                     "IPv6Address": ""
                 }
             },
             "Options": {},
             "Labels": {}
        }
]

问题：

• 为什么 docker 在用户定义的 docker 网络中使用主机搜索域？
• 为什么网络别名不可解析？
• 与CentOS 8.2版本有关吗？
• 如何解决？或如何使它工作？

谢谢

标签： dockercentos8

Answer 1

sudo firewall-cmd --permanent --zone=public --add-masquerade