Docker 1.10通过主机名通过其主机名访问容器 [英] Docker 1.10 access a container by its hostname from a host machine

问题描述

我有带有嵌入式DNS服务的Docker 1.10版本。

I have the Docker version 1.10 with embedded DNS service.

我在docker-compose文件中创建了两个服务容器。它们可以通过主机名和IP相互访问，但是当我想从主机访问它们中的一个时，它不起作用，它仅适用于IP，不适用于主机名。

I have created two service containers in my docker-compose file. They are reachable each other by hostname and by IP, but when I would like reach one of them from the host machine, it doesn't work, it works only with IP but not with hostname.

那么，能否通过Docker 1.10中的主机名从主机访问Docker容器？

So, is it possible to access a docker container from the host machine by it's hostname in the Docker 1.10, please?

更新：

docker-compose.yml

docker-compose.yml

version: '2'
services:
    service_a:
        image: nginx
        container_name: docker_a
        ports:
           - 8080:80
    service_b:
        image: nginx
        container_name: docker_b
        ports:
            - 8081:80

然后我通过命令启动它： docker-compose up --force-recreate

then I start it by command: docker-compose up --force-recreate

当我运行时：

• docker exec -i -t docker_a ping- c4 docker_b -有效


• docker exec -i -t docker_b ping -c4 docker_a -有效


• ping 172.19.0.2 -它可以正常工作（ 172.19.0.2 是 docker_b 的ip）


• ping docker_a -失败

• docker exec -i -t docker_a ping -c4 docker_b - it works
• docker exec -i -t docker_b ping -c4 docker_a - it works
• ping 172.19.0.2 - it works (172.19.0.2 is docker_b's ip)
• ping docker_a - fails

docker网络检查test_default的结果是

[
    {
        "Name": "test_default",
        "Id":   "f6436ef4a2cd4c09ffdee82b0d0b47f96dd5aee3e1bde068376dd26f81e79712",
        "Scope": "local",
        "Driver": "bridge",
        "IPAM": {
            "Driver": "default",
            "Options": null,
            "Config": [
                {
                    "Subnet": "172.19.0.0/16",
                    "Gateway": "172.19.0.1/16"
                }
            ]
        },
        "Containers": {
             "a9f13f023761123115fcb2b454d3fd21666b8e1e0637f134026c44a7a84f1b0b": {
                "Name": "docker_a",
                "EndpointID":     "a5c8e08feda96d0de8f7c6203f2707dd3f9f6c3a64666126055b16a3908fafed",
                "MacAddress": "02:42:ac:13:00:03",
                "IPv4Address": "172.19.0.3/16",
                "IPv6Address": ""
            },
                "c6532af99f691659b452c1cbf1693731a75cdfab9ea50428d9c99dd09c3e9a40": {
                "Name": "docker_b",
                "EndpointID":     "28a1877a0fdbaeb8d33a290e5a5768edc737d069d23ef9bbcc1d64cfe5fbe312",
                "MacAddress": "02:42:ac:13:00:02",
                "IPv4Address": "172.19.0.2/16",
                "IPv6Address": ""
            }
        },
        "Options": {}
    }
]

推荐答案

这就是我的工作。

我编写了一个名为 dnsthing 的Python脚本，该脚本侦听Docker事件API中有关容器启动或停止的信息。它维护一个 hosts 样式的文件，其中包含容器的名称和地址。容器名为< container_name>。< network> .docker ，因此例如，如果我运行以下命令：

I wrote a Python script called dnsthing, which listens to the Docker events API for containers starting or stopping. It maintains a hosts-style file with the names and addresses of containers. Containers are named <container_name>.<network>.docker, so for example if I run this:

docker run --rm --name mysql -e MYSQL_ROOT_PASSWORD=secret  mysql

我明白了：

172.17.0.2 mysql.bridge.docker

然后我运行 dnsmasq 进程，指向该主机文件。具体来说，我使用以下配置运行dnsmasq实例：

I then run a dnsmasq process pointing at this hosts file. Specifically, I run a dnsmasq instance using the following configuration:

listen-address=172.31.255.253
bind-interfaces
addn-hosts=/run/dnsmasq/docker.hosts
local=/docker/
no-hosts
no-resolv

然后我运行 dnsthing 脚本，如下所示：

And I run the dnsthing script like this:

dnsthing -c "systemctl restart dnsmasq_docker" \
  -H /run/dnsmasq/docker.hosts --verbose

所以：

• dnsthing 将 /run/dnsmasq/docker.hosts 更新为容器
  停止/启动


• 更新后， dnsthing 运行 systemctl重新启动dnsmasq_docker


• dnsmasq_docker 使用以上配置运行 dnsmasq ，将
  绑定到地址为 172.31的本地网桥接口.255.253 。



• 我系统上的主 dnsmasq进程由
  NetworkManager维护，使用
  /etc/NetworkManager/dnsmasq.d/dockerdns 中的配置：

• dnsthing updates /run/dnsmasq/docker.hosts as containers stop/start
• After an update, dnsthing runs systemctl restart dnsmasq_docker
• dnsmasq_docker runs dnsmasq using the above configuration, bound to a local bridge interface with the address 172.31.255.253.

• The "main" dnsmasq process on my system, maintained by NetworkManager, uses this configuration from /etc/NetworkManager/dnsmasq.d/dockerdns:

server=/docker/172.31.255.253

这告诉dnsmasq传递所有请求用于 .docker
域中的主机到 docker_dnsmasq 服务的主机。

That tells dnsmasq to pass all requests for hosts in the .docker domain to the docker_dnsmasq service.

显然，这需要一些设置才能将所有内容放在一起，但是之后
似乎就可以正常工作了：

This obviously requires a bit of setup to put everything together, but after that it seems to Just Work:

$ ping -c1  mysql.bridge.docker
PING mysql.bridge.docker (172.17.0.2) 56(84) bytes of data.
64 bytes from 172.17.0.2: icmp_seq=1 ttl=64 time=0.087 ms

--- mysql.bridge.docker ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.087/0.087/0.087/0.000 ms

这篇关于Docker 1.10通过主机名通过其主机名访问容器的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！