Docker DNS getaddrinfo ENOTFOUND [英] Docker DNS getaddrinfo ENOTFOUND

问题描述

我正在运行docker-compose with node：4.2.1-wheezy 和 dnsdock containers。

I am running docker-compose with node:4.2.1-wheezy and dnsdock containers.

我有$ code> DOCKER_OPTS = - dns 172.17.42.1 in / etc / default / docker。

I have DOCKER_OPTS="--dns 172.17.42.1" inside /etc/default/docker.

在我的node.js容器内运行 node -erequire（'dns'）。resolve（'host_name_here'）主机通过172.17.42.1 dns服务器正确解析。

When I run node -e "require('dns').resolve('host_name_here')" inside my node.js container the host is resolved correctly through the 172.17.42.1 dns server.

但是当我运行 node -erequire（'dns'）。lookup （'host_name_here'）它失败， ENOTFOUND 错误。

But when I run node -e "require('dns').lookup('host_name_here')" it fails with ENOTFOUND error.

是 http.request 使用 dns.lookup 而不是 dns.resolve 。

文档说 dns.lookup 调用 getaddrinfo 。而且据我所知 getaddrinfo 缓存/etc/resolv.conf，也许它缓存空/etc/resolv.conf（但$ code> cat / etc / resolv.conf 打印 nameserver 172.17.42.1 ）。

The docs say that dns.lookup calls getaddrinfo. And as far as I understand getaddrinfo caches /etc/resolv.conf and maybe it caches empty /etc/resolv.conf (but cat /etc/resolv.conf prints nameserver 172.17.42.1).

我真的不知道如何解决这个问题。什么可以导致这种行为？

I really have no idea how to resolve this issue. What can cause such behavior?

更新1。

docker -v
Docker version 1.7.1, build 786b29d

docker-compose -v
docker-compose version: 1.4.2

更新2。

将所有内容更新到最新版本（docker 1.9.0，docker-compose 1.5.0和节点高达5.0.0），但问题仍然存在。

I updated all things to the latest versions (docker 1.9.0, docker-compose 1.5.0 and node up to 5.0.0) but the issue still persists.

所以这是重现问题的docker-compose.yml：

So this is the docker-compose.yml that reproduces the issue:

dnsdock:
  image: tonistiigi/dnsdock
  volumes:
    - /var/run/docker.sock:/run/docker.sock
  ports:
    - "172.17.42.1:53:53/udp"
  environment:
    - DNSDOCK_ALIAS=dns.org
node:
  image: node:5.0.0-wheezy
  command: node -e "setTimeout(function () { var dns = require('dns'); dns.resolve('dns.org', console.log.bind(console, 'resolve')); dns.lookup('dns.org', console.log.bind(console, 'lookup')); }, 5000)"
  dns: 172.17.42.1

您应该替换 172.17.42.1 与您的docker0接口的IP，需要 setTimeout（...，5000），因为节点容器可能在 dnsdock 之前开始。

You should replace 172.17.42.1 with IP of your docker0 interface. The setTimeout(..., 5000) is needed because node container may start before dnsdock.

这是我的 docker-compose up 输出：

Creating test_node_1
Creating test_dnsdock_1
Attaching to test_node_1, test_dnsdock_1
dnsdock_1 | 2015/11/07 09:29:44 Added service: 3653951cff40c06c04b9ab3f5d2fc94ccc19305eaac7ba1a545ce1dbab3e3e17 {test_dnsdock_1 dnsdock 172.17.42.3 -1 [dns.org]}
dnsdock_1 | 2015/11/07 09:29:44 Added service: 36577feea136bc713f77b64b2a6a9712cd509c47ca55427f6749308cc5a4b140 {test_node_1 node 172.17.42.2 -1 []}
node_1    | resolve null [ '172.17.42.3' ]
node_1    | lookup { [Error: getaddrinfo ENOTFOUND dns.org]
node_1    |   code: 'ENOTFOUND',
node_1    |   errno: 'ENOTFOUND',
node_1    |   syscall: 'getaddrinfo',
node_1    |   hostname: 'dns.org' }
dnsdock_1 | 2015/11/07 09:29:49 Stopped service: 36577feea136bc713f77b64b2a6a9712cd509c47ca55427f6749308cc5a4b140
test_node_1 exited with code 0

推荐答案

为了更好的dns查找，您可以考虑使用网络覆盖，如 Docker覆盖网络：很简单

For a better dns lookup, you could consider using a network overlay, as presented in "Docker Overlay Networks: That was Easy"

它使用KV / Value）存储基于领事馆，和一个群集，您可以在其中注册节点。

It uses a KV (Key/Value) store bases on Consul, and a swarm cluster where you can register your nodes.

您可以构建覆盖网络

eval "$(docker-machine env --swarm c0-master)"
docker network create -d overlay myStack1

并使用它来运行图像：

docker run -d --name web --net myStack1 nginx
docker run -itd --name shell1 --net myStack1 alpine /bin/sh

容器将被附加到同一个网络，并且可以通过容器名称（不管启动顺序）来发现。

此外，当容器重新启动时，它将保持可被发现，而不必重新启动。

Both of these containers will be attached to the same network, and be discoverable by container name (regardless of start order).
Further, when a container is restarted it will remain discoverable without cascading restarts.

这篇关于Docker DNS getaddrinfo ENOTFOUND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！