为什么 Jenkins 用户可能没有访问 Docker unix socket 的权限？

Question

我已将jenkins用户添加到docker组中，认为它会允许 Jenkins 作业运行 Docker 命令。如果我切换到jenkins用户，我可以验证它是否有效（手动）：

ubuntu@hostname:~$ ps aux | grep java
jenkins   2210  9.5  7.5 1950316 292896 ?      Sl   00:01   1:00 /usr/bin/java -jar /data/jenkins/jenkins-1.586.war --httpPort=8080 -Xloggc:/var/log/jenkins/gc.log
ubuntu@hostname:~$ getent group docker
docker:x:999:jenkins
ubuntu@hostname:~$ ls -la /var/run/docker.*
-rw-r--r-- 1 root root   4 Oct 23 18:32 /var/run/docker.pid
srw-rw---- 1 root docker 0 Oct 23 18:32 /var/run/docker.sock
ubuntu@hostname:~$ sudo su -s /bin/bash jenkins
jenkins@hostname:/home/ubuntu$ docker ps
CONTAINER ID        IMAGE                      COMMAND                CREATED             STATUS              PORTS                     NAMES

但是，在 Jenkins 构建/作业期间，它没有权限：

# Job log
Started by user Matt Wright
Building on master in workspace /data/jenkins/jobs/docker-base-images-build/workspace
[ssh-agent] Using credentials CI-jenkins
[ssh-agent] Looking for ssh-agent implementation...
[ssh-agent]   Java/JNR ssh-agent
[ssh-agent] Started.
 > git rev-parse --is-inside-work-tree # timeout=10
Fetching changes from the remote Git repository
 > git config remote.origin.url git@github.com:<redacted>/docker-base-images.git # timeout=10
Fetching upstream changes from git@github.com:<redacted>/docker-base-images.git
 > git --version # timeout=10
using GIT_SSH to set credentials 
 > git fetch --tags --progress git@github.com:<redacted>/docker-base-images.git +refs/heads/*:refs/remotes/origin/*
 > git rev-parse refs/remotes/origin/master^{commit} # timeout=10
 > git rev-parse refs/remotes/origin/origin/master^{commit} # timeout=10
Checking out Revision 83c4463e7195b412a3a803dd7338210c1a772f55 (refs/remotes/origin/master)
 > git config core.sparsecheckout # timeout=10
 > git checkout -f 83c4463e7195b412a3a803dd7338210c1a772f55
 > git rev-list 83c4463e7195b412a3a803dd7338210c1a772f55 # timeout=10
[workspace] $ /bin/sh -xe /tmp/hudson5606381166745886966.sh
+ ./build.sh
Sending build context to Docker daemon 
2014/10/24 16:14:18 Post http:///var/run/docker.sock/v1.15/build?rm=1&t=<redacted>%2Fpython%3A3.4: dial unix /var/run/docker.sock: permission denied
Build step 'Execute shell' marked build as failure
[ssh-agent] Stopped.
Notifying upstream projects of job completion
Finished: FAILURE

这是 Docker 1.3.0 和 Ubuntu 14.04.1。有什么线索吗？

Answer 1

我认为将 jenkins 组权限授予 docker unix socket 解决了这个问题。这可以通过添加这一行在配置文件中配置 docker daemon 启动选项来修改

DOCKER_OPTS=' -G jenkins'

在 ubuntu 中/etc/default/docker是 docker 配置文件。