Daoker

Daoker is a tool to manage Docker environment regardless of docker daemon's failure.

Docker is an open source project to build, ship and run any application as a lightweight container. If you have some experience in operating Docker in developing, testing or production environment, you will find that the architecture of Docker is composed of four parts: Docker CLI, Docker Daemon, Docker Images and Docker Container.

Background

I believe that Docker is totally production-ready, while we still run into some cases that Docker Daemon does not work as we wish, such as :

command docker ps hangs
command docker inspect hangs
no details about docker environment, no right to talk about management
and so on

If situations above happen to you, we can judge that you lose the control of docker. If it is your developing environment, you can change a machine with Docker to avoid some problems. And if it is production environment, I think everyone should realized the gravity of this situation.

Principles

As Docker Daemon fails, we have no idea about whether docker api is working which seems so disappointing. Disappointing, but not fatal.

Have you ever experienced that Docker Daemon stores almost all details about Docker Container in its local filesystem? If the answer is "Yes", you've got what I am going to do.

Following is two most important principles:

NEVER to contact with docker daemon
take advantage of DOCKER_ROOT and CGROUP FILESYSTEM to do everything you want

Get Started

Daoker is CLI tool to handle tough things when docker daemon fails. We had better read daoker help to get more instruments.

root@daocloud:~/daoker# daoker help
NAME:
   daoker - A tool to manage Docker environment when Docker fails

USAGE:
   daoker [global options] command [command options] [arguments...]

VERSION:
   0.0.1

AUTHOR(S):
   Allen Sun <allen.sun@daocloud.io>

COMMANDS:
    ps		List containers
    kill	Stop a container forcefully
    stop	Stop a container
    volume	Show all details of a container's volumes
    pid		Print container name if it contains the given pid
    oom		Return true if a container is under oom
    pidnum	Print process numbers in your specified container

GLOBAL OPTIONS:
   --debug			debug mode [$DEBUG]
   --log-level, -l "info"	Log level (options: debug, info, warn, error, fatal, panic)
   --help, -h			show help
   --version, -v		print the version

Then enjoy your jouney with daoker if you happen to find some commands are helpful to you.

Build and Install Daoker

Before you Build and Install daoker, you should know some prerequisition:

Linux only
Ubuntu preferred
Golang 1.5+ preferred
Docker 1.10.0+ tested, lower version will be tested soon

git clone https://github.com/allencloud/daoker.git
cd daoker
export GOPATH=`pwd`
go get -d
go build -o daoker

mv daoker /usr/local/bin

Now daoker is in your PATH.

Participating

You can contribute to Daoker in several different ways:

To report a problem or request a feature, please feel free to file an issue.
Of course, we welcome pull requests and patches. Setting up a local Daoker development environment and submitting PRs is described here.