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Author SHA1 Message Date
Hongli Lai (Phusion)
0caf8692fb Update Changelog 2014-02-17 12:01:09 +01:00
Hongli Lai (Phusion)
d8968d136a Improve setuser: set auxilliary groups and more environment variables 2014-02-15 12:42:31 +01:00
Hongli Lai (Phusion)
b6dac86e04 Improve the init system: support skipping startup files and running a custom main command 2014-02-15 12:11:48 +01:00
Hongli Lai (Phusion)
d884118827 Add a 'make ssh' task for easily SSHing into the container 2014-02-13 15:37:35 +01:00
Hongli Lai (Phusion)
c22f8804ad Correctly reap child processes that are adopted during invocation of init scripts. 2014-02-13 15:37:32 +01:00
Hongli Lai (Phusion)
67c6b089e3 Bump version to 0.9.6 2014-02-13 15:37:32 +01:00
Hongli Lai (Phusion)
7e35fe7f32 Update Changelog 2014-02-06 14:00:18 +01:00
Hongli Lai (Phusion)
37cd856425 Disable the insecure SSH key by default 2014-02-06 13:40:27 +01:00
Hongli Lai (Phusion)
a5f521b1b1 Change the name inside the insecure key 2014-02-06 13:06:40 +01:00
Hongli Lai (Phusion)
e833b26944 Bump version to 0.9.5 2014-02-06 13:06:23 +01:00
Hongli Lai (Phusion)
4ab0625de0 Update README 2014-02-06 12:36:06 +01:00
Hongli Lai (Phusion)
a8db7a386f Update Changelog 2014-02-06 12:32:39 +01:00
Hongli Lai (Phusion)
f0fbe3ffc8 Use setuser instead of chpst in the memcached example for consistency. Closes GH-8 2014-02-06 12:31:07 +01:00
Hongli Lai
4a6ee64b63 Merge pull request #6 from yukonlabs/master
Bypass runsvdir-start in order to preserve env
2014-02-06 12:30:51 +01:00
Matt Olson
892dcc7ca4 Bypass runsvdir-start in order to preserve env
runsvdir-start clears the environment, which wipes out any
environment variables passed in when the container starts.
This patch bypasses runsvdir-start and calls runsvdir directly,
preserving the current environment.
2014-02-05 11:52:48 -08:00
Hongli Lai (Phusion)
c844956bab Release 0.9.4 2014-02-03 17:07:09 +01:00
Hongli Lai (Phusion)
3e14c92e21 Bump version to 0.9.4 2014-02-03 17:03:44 +01:00
Hongli Lai (Phusion)
6786e7350d Fixed syslog-ng startup problem 2014-02-03 17:03:39 +01:00
Hongli Lai (Phusion)
b17412ef7c Run tests on release 2014-02-03 17:02:59 +01:00
Hongli Lai (Phusion)
1463b81942 Add unit tests 2014-02-03 17:01:11 +01:00
Hongli Lai (Phusion)
64c7d8be7c Update README 2014-02-02 13:32:39 +01:00
Hongli Lai (Phusion)
06e46b93cf Update README 2014-02-02 13:31:51 +01:00
Hongli Lai (Phusion)
b297ae8b42 Add table of contents to README. 2014-02-01 11:33:34 +01:00
Hongli Lai (Phusion)
017c6c22d5 Add a Changelog entry documenting the SSH host key change 2014-02-01 11:10:23 +01:00
Hongli Lai (Phusion)
74a4a9abf4 Note release date for 0.9.3 2014-02-01 11:08:39 +01:00
Hongli Lai (Phusion)
d2d1f713a4 Add forgotten file 2014-01-31 19:29:50 +01:00
Hongli Lai (Phusion)
4ee9947467 Correctly mount passenger-docker in Vagrantfile 2014-01-31 16:04:00 +01:00
Hongli Lai (Phusion)
abf75875a9 Do not save SSH host key in baseimage-docker. Instead, generate it automatically during boot. 2014-01-31 16:02:01 +01:00
Hongli Lai (Phusion)
d2b28d25a6 Bump version to 0.9.3 2014-01-31 15:46:59 +01:00
Hongli Lai (Phusion)
62859010cb Allow running scripts during startup. 2014-01-31 15:44:50 +01:00
Hongli Lai (Phusion)
2ac41ee8ab Fix compatibility with latest Ubuntu 12.04 base image. 2014-01-31 15:08:27 +01:00
Hongli Lai (Phusion)
4a3569a9cb Add license 2014-01-14 20:29:45 +01:00
Hongli Lai (Phusion)
8222745ad8 Fix typo in README 2014-01-09 23:21:40 +01:00
Hongli Lai (Phusion)
009ed4bd5e Release version 0.9.2 2013-12-11 21:56:29 +01:00
Hongli Lai
5a65631322 Merge pull request #2 from jorisvddonk/patch-1
Fixed SFTP not working
2013-12-06 05:14:35 -08:00
Joris van de Donk
0bcc88828e Fixed SFTP not working
sftp-server isn't located under `/usr/libexec/` (the directory doesn't exist). It's instead located at `/usr/lib/sftp-server`
2013-12-06 13:32:57 +01:00
Hongli Lai (Phusion)
67a9684f0a Fix typos in README 2013-11-20 15:52:18 +01:00
Hongli Lai (Phusion)
c7eb6e98e2 Revert "Document another reason why SSH access is important"
This reverts commit c51ba582e9.
2013-11-13 12:13:06 +01:00
Hongli Lai (Phusion)
c51ba582e9 Document another reason why SSH access is important 2013-11-13 11:42:21 +01:00
Hongli Lai (Phusion)
5293343735 Update README again 2013-11-13 01:04:53 +01:00
Hongli Lai (Phusion)
12e0c8f601 Update README again 2013-11-13 00:07:26 +01:00
Hongli Lai (Phusion)
22fc313d91 Make the description clearer to people who are not familiar with the problem domain 2013-11-12 23:58:05 +01:00
Hongli Lai (Phusion)
4156ab3393 Update README 2013-11-12 23:26:37 +01:00
16 changed files with 573 additions and 102 deletions

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@@ -1,3 +1,32 @@
## 0.9.6 (release date: 2014-02-17)
* Fixed a bug in `my_init`: child processes that have been adopted during execution of init scripts are now properly reaped.
* Much improved `my_init`:
* It is now possible to run and watch a custom command, possibly in addition to running runit. See "Running a one-shot command in the container" in the README.
* It is now possible to skip running startup files such as /etc/rc.local.
* Shutdown is not much faster. It previously took a few seconds, but it is now almost instantaneous.
* It ensures that all processes in the container are properly shut down with SIGTERM, even those that are not direct child processes of `my_init`.
* `setuser` now also sets auxilliary groups, as well as more environment variables such as `USER` and `UID`.
## 0.9.5 (release date: 2014-02-06)
* Environment variables are now no longer reset by runit. This is achieved by running `runsvdir` directly instead of through Debian's `runsvdir-start`.
* The insecure SSH key is now disabled by default. You have to explicitly opt-in to use it.
## 0.9.4 (release date: 2014-02-03)
* Fixed syslog-ng startup problem.
## 0.9.3 (release date: 2014-01-31)
* It looks like Docker changed their Ubuntu 12.04 base image, thereby breaking our Dockerfile. This has been fixed.
* The init system (`/sbin/my_init`) now supports running scripts during startup. You can put startup scripts `/etc/my_init.d`. `/etc/rc.local` is also run during startup.
* To improve security, the base image no longer contains pregenerated SSH host keys. Instead, users of the base image are encouraged to regenerate one in their Dockerfile. If the user does not do that, then random SSH host keys are generated during container boot.
## 0.9.2 (release date: 2013-12-11)
* Fixed SFTP support. Thanks Joris van de Donk!
## 0.9.1 (release date: 2013-11-12) ## 0.9.1 (release date: 2013-11-12)
* Improved init process script (`/sbin/my_init`): it now handles shutdown correctly. Previously, `docker stop` would not have any effect on `my_init`, causing the whole container to be killed with SIGKILL. The new init process script gracefully shuts down all runit services, then exits. * Improved init process script (`/sbin/my_init`): it now handles shutdown correctly. Previously, `docker stop` would not have any effect on `my_init`, causing the whole container to be killed with SIGKILL. The new init process script gracefully shuts down all runit services, then exits.

19
LICENSE.txt Normal file
View File

@@ -0,0 +1,19 @@
Copyright (c) 2013-2014 Phusion
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

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@@ -1,17 +1,28 @@
NAME = phusion/baseimage NAME = phusion/baseimage
VERSION = 0.9.1 VERSION = 0.9.6
.PHONY: all build tag_latest release .PHONY: all build test tag_latest release ssh
all: build all: build
build: build:
docker build -t $(NAME):$(VERSION) -rm image docker build -t $(NAME):$(VERSION) -rm image
test:
env NAME=$(NAME) VERSION=$(VERSION) ./test/runner.sh
tag_latest: tag_latest:
docker tag $(NAME):$(VERSION) $(NAME):latest docker tag $(NAME):$(VERSION) $(NAME):latest
release: tag_latest release: test tag_latest
@if ! docker images phusion/baseimage | awk '{ print $$2 }' | grep -q -F $(VERSION); then echo "$(NAME) version $(VERSION) is not yet built. Please run 'make build'"; false; fi @if ! docker images phusion/baseimage | awk '{ print $$2 }' | grep -q -F $(VERSION); then echo "$(NAME) version $(VERSION) is not yet built. Please run 'make build'"; false; fi
docker push $(NAME) docker push $(NAME)
@echo "*** Don't forget to create a tag. git tag rel-$(VERSION) && git push origin rel-$(VERSION)" @echo "*** Don't forget to create a tag. git tag rel-$(VERSION) && git push origin rel-$(VERSION)"
ssh:
chmod 600 image/insecure_key.pub
@ID=$$(docker ps | grep -F "$(NAME):$(VERSION)" | awk '{ print $$1 }') && \
if test "$$ID" = ""; then echo "Container is not running."; exit 1; fi && \
IP=$$(docker inspect $$ID | grep IPAddr | sed 's/.*: "//; s/".*//') && \
echo "SSHing into $$IP" && \
ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -i image/insecure_key root@$$IP

189
README.md
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@@ -1,23 +1,57 @@
# A minimal Docker base image with a correct and usable system # A minimal Ubuntu base image modified for Docker-friendliness
Baseimage-docker is a [Docker](http://www.docker.io) image meant to serve as a good base for any other Docker container. It contains a minimal base system with the most important things already installed and set up correctly. Baseimage-docker is a special [Docker](http://www.docker.io) image that is configured for correct use within Docker containers. It is Ubuntu, plus modifications for Docker-friendliness. You can use it as a base for your own Docker images.
* **Github**: https://github.com/phusion/baseimage-docker Baseimage-docker is available for pulling from [the Docker registry](https://index.docker.io/u/phusion/baseimage/)!
* **Docker registry entry**: https://index.docker.io/u/phusion/baseimage/
* **Discussion forum**: https://groups.google.com/d/forum/passenger-docker
* **Twitter**: https://twitter.com/phusion_nl
* **Blog**: http://blog.phusion.nl/
### What are the problems with the stock Ubuntu base image?
Ubuntu is not designed to be run inside docker. Its init system, Upstart, assumes that it's running on either real hardware or virtualized hardware, but not inside a Docker container. But inside a container you don't want a full system anyway, you want a minimal system. But configuring that minimal system for use within a container has many strange corner cases that are hard to get right if you are not intimately familiar with the Unix system model. This can cause a lot of strange problems.
Baseimage-docker gets everything right. The "Contents" section describes all the things that it modifies.
<a name="why_use"></a>
### Why use baseimage-docker? ### Why use baseimage-docker?
Why use baseimage-docker instead of doing everything yourself in Dockerfile? You can configure the stock `ubuntu` image yourself from your Dockerfile, so why bother using baseimage-docker?
* Configuring the base system for Docker-friendliness is no easy task. As stated before, there are many corner cases. By the time that you've gotten all that right, you've reinvented baseimage-docker. Using baseimage-docker will save you from this effort.
* It reduces the time needed to write a correct Dockerfile. You won't have to worry about the base system and can focus on your stack and your app. * It reduces the time needed to write a correct Dockerfile. You won't have to worry about the base system and can focus on your stack and your app.
* It sets up the base system **correctly**. It's very easy to get the base system wrong, but this image does everything correctly.
* It reduces the time needed to run `docker build`, allowing you to iterate your Dockerfile more quickly. * It reduces the time needed to run `docker build`, allowing you to iterate your Dockerfile more quickly.
* It reduces download time during redeploys. Docker only needs to download the base image once: during the first deploy. On every subsequent deploys, only the changes you make on top of the base image are downloaded. * It reduces download time during redeploys. Docker only needs to download the base image once: during the first deploy. On every subsequent deploys, only the changes you make on top of the base image are downloaded.
## Contents -----------------------------------------
**Related resources**:
[Website](http://phusion.github.io/baseimage-docker/) |
[Github](https://github.com/phusion/baseimage-docker) |
[Docker registry](https://index.docker.io/u/phusion/baseimage/) |
[Discussion forum](https://groups.google.com/d/forum/passenger-docker) |
[Twitter](https://twitter.com/phusion_nl) |
[Blog](http://blog.phusion.nl/)
**Table of contents**
* [What's inside the image?](#whats_inside)
* [Overview](#whats_inside_overview)
* [Wait, I thought Docker is about running a single process in a container?](#docker_single_process)
* [Inspecting baseimage-docker](#inspecting)
* [Using baseimage-docker as base image](#using)
* [Getting started](#getting_started)
* [Adding additional daemons](#adding_additional_daemons)
* [Running scripts during container startup](#running_startup_scripts)
* [Running a one-shot command in the container](#oneshot)
* [Login to the container via SSH](#login)
* [Building the image yourself](#building)
* [Conclusion](#conclusion)
-----------------------------------------
<a name="whats_inside"></a>
## What's inside the image?
<a name="whats_inside_overview"></a>
### Overview
*Looking for a more complete base image, one that is ideal for Ruby, Python, Node.js and Meteor web apps? Take a look at [passenger-docker](https://github.com/phusion/passenger-docker).* *Looking for a more complete base image, one that is ideal for Ruby, Python, Node.js and Meteor web apps? Take a look at [passenger-docker](https://github.com/phusion/passenger-docker).*
@@ -27,19 +61,21 @@ Why use baseimage-docker instead of doing everything yourself in Dockerfile?
| A **correct** init process | According to the Unix process model, [the init process](https://en.wikipedia.org/wiki/Init) -- PID 1 -- inherits all [orphaned child processes](https://en.wikipedia.org/wiki/Orphan_process) and must [reap them](https://en.wikipedia.org/wiki/Wait_(system_call). Most Docker containers do not have an init process that does this correctly, and as a result their containers become filled with [zombie processes](https://en.wikipedia.org/wiki/Zombie_process) over time. <br><br>Furthermore, `docker stop` sends SIGTERM to the init process, which is then supposed to stop all services. Unfortunately most init systems don't do this correctly within Docker since they're built for hardware shutdowns instead. This causes processes to be hard killed with SIGKILL, which doesn't give them a chance to correctly deinitialize things. This can cause file corruption. <br><br>Baseimage-docker comes with an init process `/sbin/my_init` that performs both of these tasks correctly. | | A **correct** init process | According to the Unix process model, [the init process](https://en.wikipedia.org/wiki/Init) -- PID 1 -- inherits all [orphaned child processes](https://en.wikipedia.org/wiki/Orphan_process) and must [reap them](https://en.wikipedia.org/wiki/Wait_(system_call). Most Docker containers do not have an init process that does this correctly, and as a result their containers become filled with [zombie processes](https://en.wikipedia.org/wiki/Zombie_process) over time. <br><br>Furthermore, `docker stop` sends SIGTERM to the init process, which is then supposed to stop all services. Unfortunately most init systems don't do this correctly within Docker since they're built for hardware shutdowns instead. This causes processes to be hard killed with SIGKILL, which doesn't give them a chance to correctly deinitialize things. This can cause file corruption. <br><br>Baseimage-docker comes with an init process `/sbin/my_init` that performs both of these tasks correctly. |
| Fixes APT incompatibilities with Docker | See https://github.com/dotcloud/docker/issues/1024. | | Fixes APT incompatibilities with Docker | See https://github.com/dotcloud/docker/issues/1024. |
| syslog-ng | A syslog daemon is necessary so that many services - including the kernel itself - can correctly log to /var/log/syslog. If no syslog daemon is running, a lot of important messages are silently swallowed. <br><br>Only listens locally. | | syslog-ng | A syslog daemon is necessary so that many services - including the kernel itself - can correctly log to /var/log/syslog. If no syslog daemon is running, a lot of important messages are silently swallowed. <br><br>Only listens locally. |
| ssh server | Allows you to easily login to your container to inspect or administer things. <br><br>Password and challenge-response authentication are disabled by default. Only key authentication is allowed.<br>It allows an predefined key by default to make debugging easy. You should replace this ASAP. See instructions. | | ssh server | Allows you to easily login to your container to inspect or administer things. <br><br>Password and challenge-response authentication are disabled by default. Only key authentication is allowed.<br>By default, it allows a predefined key, in order to make debugging easy. You should replace this ASAP. See instructions. |
| cron | The cron daemon must be running for cron jobs to work. | | cron | The cron daemon must be running for cron jobs to work. |
| [runit](http://smarden.org/runit/) | For service supervision and management. Much easier to use than SysV init and supports restarting daemons when they crash. Much easier to use and more lightweight than Upstart. | | [runit](http://smarden.org/runit/) | Replaces Ubuntu's Upstart. Used for service supervision and management. Much easier to use than SysV init and supports restarting daemons when they crash. Much easier to use and more lightweight than Upstart. |
| `setuser` | A tool for running a command as another user. Easier to use than `su`, has a smaller attack vector than `sudo`, and unlike `chpst` this tool sets `$HOME` correctly. Available as `/sbin/setuser`. | | `setuser` | A tool for running a command as another user. Easier to use than `su`, has a smaller attack vector than `sudo`, and unlike `chpst` this tool sets `$HOME` correctly. Available as `/sbin/setuser`. |
Baseimage-docker is very lightweight: it only consumes 6 MB of memory. Baseimage-docker is very lightweight: it only consumes 6 MB of memory.
<a name="docker_single_process"></a>
### Wait, I thought Docker is about running a single process in a container? ### Wait, I thought Docker is about running a single process in a container?
Absolutely not true. Docker runs fine with multiple processes in a container. In fact, there is no technical reason why you should limit yourself to one process - it only makes things harder for you and breaks all kinds of essential system functionality, e.g. syslog. Absolutely not true. Docker runs fine with multiple processes in a container. In fact, there is no technical reason why you should limit yourself to one process - it only makes things harder for you and breaks all kinds of essential system functionality, e.g. syslog.
Baseimage-docker *encourages* multiple processes through the use of runit. Baseimage-docker *encourages* multiple processes through the use of runit.
<a name="inspecting"></a>
## Inspecting baseimage-docker ## Inspecting baseimage-docker
To look around in the image, run: To look around in the image, run:
@@ -48,11 +84,13 @@ To look around in the image, run:
You don't have to download anything manually. The above command will automatically pull the baseimage-docker image from the Docker registry. You don't have to download anything manually. The above command will automatically pull the baseimage-docker image from the Docker registry.
<a name="using"></a>
## Using baseimage-docker as base image ## Using baseimage-docker as base image
The image is called `phusion/baseimage`, and is available on the Docker registry. <a name="getting_started"></a>
### Getting started
By default, it allows SSH access for the key in `image/insecure_key`. This makes it easy for you to login to the container, but you should replace this key as soon as possible. The image is called `phusion/baseimage`, and is available on the Docker registry.
# Use phusion/baseimage as base image. To make your builds reproducible, make # Use phusion/baseimage as base image. To make your builds reproducible, make
# sure you lock down to a specific version, not to `latest`! # sure you lock down to a specific version, not to `latest`!
@@ -63,44 +101,125 @@ By default, it allows SSH access for the key in `image/insecure_key`. This makes
# Set correct environment variables. # Set correct environment variables.
ENV HOME /root ENV HOME /root
# Remove authentication rights for insecure_key. # Regenerate SSH host keys. baseimage-docker does not contain any, so you
RUN rm -f /root/.ssh/authorized_keys /home/*/.ssh/authorized_keys # have to do that yourself. You may also comment out this instruction; the
# init system will auto-generate one during boot.
RUN /etc/my_init.d/00_regen_ssh_host_keys.sh
# Use baseimage-docker's init process. # Use baseimage-docker's init system.
CMD ["/sbin/my_init"] CMD ["/sbin/my_init"]
# ...put other build instructions here... # ...put your own build instructions here...
# Clean up APT when done. # Clean up APT when done.
RUN apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* RUN apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
<a name="adding_additional_daemons"></a>
### Adding additional daemons ### Adding additional daemons
You can add additional daemons to the image by creating runit entries. You only have to write a small shell script which runs your daemon, and runit will keep it up and running for you, restarting it when it crashes, etc. You can add additional daemons (e.g. your own app) to the image by creating runit entries. You only have to write a small shell script which runs your daemon, and runit will keep it up and running for you, restarting it when it crashes, etc.
The shell script must be called `run`, must be executable, and is to be placed in the directory `/etc/services/<NAME>`. The shell script must be called `run`, must be executable, and is to be placed in the directory `/etc/service/<NAME>`.
Here's an example showing you how to a memached server runit entry can be made. Here's an example showing you how to a memached server runit entry can be made.
### In memcached.sh (make sure this file is chmod +x): ### In memcached.sh (make sure this file is chmod +x):
#!/bin/sh #!/bin/sh
# `chpst` is part of running. `chpst -u memcache` runs the given command # `/sbin/setuser memcache` runs the given command as the user `memcache`.
# as the user `memcache`. If you omit this, the command will be run as root. # If you omit that part, the command will be run as root.
exec chpst -u memcache /usr/bin/memcached >>/var/log/memcached.log 2>&1 exec /sbin/setuser memcache /usr/bin/memcached >>/var/log/memcached.log 2>&1
### In Dockerfile: ### In Dockerfile:
RUN mkdir /etc/services/memcached RUN mkdir /etc/service/memcached
ADD redis.sh /etc/services/memcached/run ADD memcached.sh /etc/service/memcached/run
Note that the shell script must run the daemon **without letting it daemonize/fork it**. Usually, daemons provide a command line flag or a config file option for that. Note that the shell script must run the daemon **without letting it daemonize/fork it**. Usually, daemons provide a command line flag or a config file option for that.
### Login in to the container <a name="running_startup_scripts"></a>
### Running scripts during container startup
The baseimage-docker init system, `/sbin/my_init`, runs the following scripts during startup, in the following order:
* All executable scripts in `/etc/my_init.d`, if this directory exists. The scripts are run during in lexicographic order.
* The script `/etc/rc.local`, if this file exists.
All scripts must exit correctly, e.g. with exit code 0. If any script exits with a non-zero exit code, the booting will fail.
The following example shows how you can add a startup script. This script simply logs the time of boot to the file /tmp/boottime.txt.
### In logtime.sh (make sure this file is chmod +x):
#!/bin/sh
date > /tmp/boottime.txt
### In Dockerfile:
RUN mkdir -p /etc/my_init.d
ADD logtime.sh /etc/my_init.d/logtime.sh
<a name="oneshot"></a>
### Running a one-shot command in the container
Normally, when you want to run a single command in a container, and exit immediately after the command, you invoke Docker like this:
docker run YOUR_IMAGE COMMAND ARGUMENTS...
However the downside of this approach is that the init system is not started. That is, while invoking `COMMAND`, important daemons such as cron and syslog are not running. Also, orphaned child processes are not properly reaped, because `COMMAND` is PID 1.
Baseimage-docker provides a facility to run a single one-shot command, while solving all of the aforementioned problems. Run a single command in the following manner:
docker run YOUR_IMAGE /sbin/my_init -- COMMAND ARGUMENTS ...
This will perform the following:
* Runs all system startup files, such as /etc/my_init.d/* and /etc/rc.local.
* Starts all runit services.
* Runs the specified command.
* When the specified command exits, stops all runit services.
For example:
$ docker run phusion/baseimage:<VERSION> /sbin/my_init -- ls
*** Running /etc/my_init.d/00_regen_ssh_host_keys.sh...
No SSH host key available. Generating one...
Creating SSH2 RSA key; this may take some time ...
Creating SSH2 DSA key; this may take some time ...
Creating SSH2 ECDSA key; this may take some time ...
*** Running /etc/rc.local...
*** Booting runit daemon...
*** Runit started as PID 80
*** Running ls...
bin boot dev etc home image lib lib64 media mnt opt proc root run sbin selinux srv sys tmp usr var
*** ls exited with exit code 0.
*** Shutting down runit daemon (PID 80)...
*** Killing all processes...
You may find that the default invocation is too noisy. Or perhaps you don't want to run the startup files. You can customize all this by passing arguments to `my_init`. Invoke `docker run YOUR_IMAGE /sbin/my_init --help` for more information.
The following example runs `ls` without running the startup files and with less messages, while running all runit services:
$ docker run phusion/baseimage:<VERSION> /sbin/my_init --skip-startup-files --quiet -- ls
bin boot dev etc home image lib lib64 media mnt opt proc root run sbin selinux srv sys tmp usr var
<a name="login"></a>
### Login to the container via SSH
You can use SSH to login to any container that is based on baseimage-docker. You can use SSH to login to any container that is based on baseimage-docker.
Start a container based on baseimage-docker (or a container based on an image based on baseimage-docker): The first thing that you need to do is to ensure that you have the right SSH keys installed inside the container. By default, no keys are installed, so you can't login. For convenience reasons, we provide [a pregenerated, insecure key](https://github.com/phusion/baseimage-docker/blob/master/image/insecure_key) that you easily enable. However, please be aware that using this key is for convenience only. It does not provide any insecurity because this key (both the public and the private side) are publicly available. In production environments, you should use your own keys.
docker run phusion/baseimage Edit your Dockerfile to install an SSH key:
## Install an SSH of your choice.
ADD your_key /tmp/your_key
RUN cat /tmp/your_key >> /root/.ssh/authorized_keys && rm -f /tmp/your_key
## -OR-
## Uncomment this to enable the insecure key.
# RUN /usr/sbin/enable_insecure_key
Then rebuild your image. Once you have that, start a container based on that image:
docker run your-image-name
Find out the ID of the container that you just ran: Find out the ID of the container that you just ran:
@@ -110,10 +229,19 @@ Once you have the ID, look for its IP address with:
docker inspect <ID> | grep IPAddress docker inspect <ID> | grep IPAddress
Now SSH into the container. In this example we're using [the default insecure key](https://github.com/phusion/baseimage-docker/blob/master/image/insecure_key), but if you're followed the instructions well then you've already replaced that with your own key. You did replace the key, didn't you? Now SSH into the container as follows:
ssh -i /path-to/your_key root@<IP address>
# -OR-
# If you're using the insecure key, download it and SSH
# into the container using that key.
curl -o insecure_key -fSL https://github.com/phusion/baseimage-docker/raw/master/image/insecure_key
chmod 700 insecure_key
ssh -i insecure_key root@<IP address> ssh -i insecure_key root@<IP address>
<a name="building"></a>
## Building the image yourself ## Building the image yourself
If for whatever reason you want to build the image yourself instead of downloading it from the Docker registry, follow these instructions. If for whatever reason you want to build the image yourself instead of downloading it from the Docker registry, follow these instructions.
@@ -137,10 +265,11 @@ If you want to call the resulting image something else, pass the NAME variable,
make build NAME=joe/baseimage make build NAME=joe/baseimage
<a name="conclusion"></a>
## Conclusion ## Conclusion
* Using baseimage-docker? [Tweet about us](https://twitter.com/share) or [follow us on Twitter](https://twitter.com/phusion_nl). * Using baseimage-docker? [Tweet about us](https://twitter.com/share) or [follow us on Twitter](https://twitter.com/phusion_nl).
* Having problems? Please post a message at [the discussion forum](https://groups.google.com/d/forum/passenger-docker). * Having problems? Want to participate in development? Please post a message at [the discussion forum](https://groups.google.com/d/forum/passenger-docker).
* Looking for a more complete base image, one that is ideal for Ruby, Python, Node.js and Meteor web apps? Take a look at [passenger-docker](https://github.com/phusion/passenger-docker). * Looking for a more complete base image, one that is ideal for Ruby, Python, Node.js and Meteor web apps? Take a look at [passenger-docker](https://github.com/phusion/passenger-docker).
[<img src="http://www.phusion.nl/assets/logo.png">](http://www.phusion.nl/) [<img src="http://www.phusion.nl/assets/logo.png">](http://www.phusion.nl/)

2
Vagrantfile vendored
View File

@@ -9,7 +9,7 @@ Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
config.vm.box = "phusion-open-ubuntu-12.04-amd64" config.vm.box = "phusion-open-ubuntu-12.04-amd64"
config.vm.box_url = "https://oss-binaries.phusionpassenger.com/vagrant/boxes/ubuntu-12.04.3-amd64-vbox.box" config.vm.box_url = "https://oss-binaries.phusionpassenger.com/vagrant/boxes/ubuntu-12.04.3-amd64-vbox.box"
config.ssh.forward_agent = true config.ssh.forward_agent = true
if File.directory?("#{ROOT}/passenger-docker") if File.directory?("#{ROOT}/../passenger-docker")
config.vm.synced_folder File.expand_path("#{ROOT}/../passenger-docker"), config.vm.synced_folder File.expand_path("#{ROOT}/../passenger-docker"),
"/vagrant/passenger-docker" "/vagrant/passenger-docker"
end end

View File

@@ -0,0 +1,6 @@
#!/bin/bash
set -e
if [[ ! -e /etc/ssh/ssh_host_rsa_key ]]; then
echo "No SSH host key available. Generating one..."
dpkg-reconfigure openssh-server
fi

View File

@@ -6,3 +6,5 @@ set -x
apt-get clean apt-get clean
rm -rf /build rm -rf /build
rm -rf /tmp/* /var/tmp/* rm -rf /tmp/* /var/tmp/*
rm -f /etc/ssh/ssh_host_*

View File

@@ -123,7 +123,7 @@ ChallengeResponseAuthentication no
#Banner none #Banner none
# override default of no subsystems # override default of no subsystems
Subsystem sftp /usr/libexec/sftp-server Subsystem sftp /usr/lib/sftp-server
# Example of overriding settings on a per-user basis # Example of overriding settings on a per-user basis
#Match User anoncvs #Match User anoncvs

17
image/enable_insecure_key Executable file
View File

@@ -0,0 +1,17 @@
#!/bin/bash
set -e
AUTHORIZED_KEYS=/root/.ssh/authorized_keys
if [[ -e "$AUTHORIZED_KEYS" ]] && grep -q baseimage-docker-insecure-key "$AUTHORIZED_KEYS"; then
echo "Insecure key has already been added to $AUTHORIZED_KEYS."
else
DIR=`dirname "$AUTHORIZED_KEYS"`
echo "Creating directory $DIR..."
mkdir -p "$DIR"
chmod 700 "$DIR"
chown root:root "$DIR"
echo "Editing $AUTHORIZED_KEYS..."
cat /etc/insecure_key.pub > "$AUTHORIZED_KEYS"
echo "Success: insecure key has been added to $AUTHORIZED_KEYS"
fi

View File

@@ -1 +1 @@
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDVmzBG5v7cO9IScGLIzlhGlHNFhXzy87VfaPzru7qnIIdQ1e9FEKvtqEws8hVixnCUdviwX5lvcMk4Ef4Tbrmj3dyF0zFtYbjiTSyl/XQlF68DQlc2sTAdHy96wJHvh7ky511tKJzzyWwSqeef4WjeVK28TqcGnq1up0S7saFO0dJh6OfDAg2cDmhyweR3VgT0vZJyrDV7hte95MBCdK+Gp7fdCyEZcWm3S1DBFaeBqHzzt/Y/njAVKbYL9TIVPum8iMg0rMiLi9ShfP+dT5Xud5Oa3dcN2OWhiDfJw5pfhFJWd44cJ/uGRwQpvNs/PNKsYABhgLlTMUH4iawhu1Xb hongli@asuna-3939 ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDVmzBG5v7cO9IScGLIzlhGlHNFhXzy87VfaPzru7qnIIdQ1e9FEKvtqEws8hVixnCUdviwX5lvcMk4Ef4Tbrmj3dyF0zFtYbjiTSyl/XQlF68DQlc2sTAdHy96wJHvh7ky511tKJzzyWwSqeef4WjeVK28TqcGnq1up0S7saFO0dJh6OfDAg2cDmhyweR3VgT0vZJyrDV7hte95MBCdK+Gp7fdCyEZcWm3S1DBFaeBqHzzt/Y/njAVKbYL9TIVPum8iMg0rMiLi9ShfP+dT5Xud5Oa3dcN2OWhiDfJw5pfhFJWd44cJ/uGRwQpvNs/PNKsYABhgLlTMUH4iawhu1Xb baseimage-docker-insecure-key

View File

@@ -1,64 +1,238 @@
#!/usr/bin/python2 #!/usr/bin/python2
import os, sys, signal, errno import os, sys, stat, signal, errno, argparse, time
def reap_child(signum, frame): KILL_PROCESS_TIMEOUT = 5
global pid, status, waiting_for_runit KILL_ALL_PROCESSES_TIMEOUT = 5
LOG_LEVEL_ERROR = 1
LOG_LEVEL_WARN = 1
LOG_LEVEL_INFO = 2
LOG_LEVEL_DEBUG = 3
log_level = None
class AlarmException(Exception):
pass
def error(message):
if log_level >= LOG_LEVEL_ERROR:
sys.stderr.write("*** %s\n" % message)
def warn(message):
if log_level >= LOG_LEVEL_WARN:
print("*** %s" % message)
def info(message):
if log_level >= LOG_LEVEL_INFO:
print("*** %s" % message)
def debug(message):
if log_level >= LOG_LEVEL_DEBUG:
print("*** %s" % message)
def ignore_signals_and_raise_keyboard_interrupt(signame):
signal.signal(signal.SIGTERM, signal.SIG_IGN)
signal.signal(signal.SIGINT, signal.SIG_IGN)
raise KeyboardInterrupt(signame)
def raise_alarm_exception():
raise AlarmException('Alarm')
def listdir(path):
try: try:
result = os.wait3(os.WNOHANG) result = os.stat(path)
if result is not None and pid == result[0]:
status = result[1]
except OSError: except OSError:
pass return []
if stat.S_ISDIR(result.st_mode):
def stop_runit(signum, frame): return sorted(os.listdir(path))
global pid
print("*** Shutting down runit (PID %d)..." % pid)
try:
os.kill(pid, signal.SIGHUP)
except OSError:
pass
# Start runit.
signal.signal(signal.SIGCHLD, reap_child)
print("*** Booting runit...")
pid = os.spawnl(os.P_NOWAIT, "/usr/sbin/runsvdir-start", "/usr/sbin/runsvdir-start")
print("*** Runit started as PID %d" % pid)
signal.signal(signal.SIGTERM, stop_runit)
# Wait for runit, and while waiting, reap any adopted orphans.
done = False
while not done:
try:
this_pid, status = os.waitpid(pid, 0)
done = True
except OSError as e:
if e.errno == errno.EINTR:
# Try again
pass
else: else:
# The SIGCHLD handler probably caught it. return []
def is_exe(path):
try:
return os.path.isfile(path) and os.access(path, os.X_OK)
except OSError:
return False
def waitpid_reap_other_children(pid):
done = False
status = None
while not done:
this_pid, status = os.waitpid(-1, 0)
done = this_pid == pid
return status
def stop_child_process(name, pid, signo = signal.SIGTERM, time_limit = KILL_PROCESS_TIMEOUT):
info("Shutting down %s (PID %d)..." % (name, pid))
try:
os.kill(pid, signo)
except OSError:
pass
signal.alarm(time_limit)
try:
try:
waitpid_reap_other_children(pid)
except OSError:
pass
except AlarmException:
warn("%s (PID %d) did not shut down in time. Forcing it to exit.")
try:
os.kill(pid, signal.SIGKILL)
except OSError:
pass
try:
waitpid_reap_other_children(pid)
except OSError:
pass
finally:
signal.alarm(0)
def run_command_killable(*argv):
filename = argv[0]
status = None
pid = os.spawnvp(os.P_NOWAIT, filename, argv)
try:
status = waitpid_reap_other_children(pid)
except BaseException as s:
warn("An error occurred. Aborting.")
stop_child_process(filename, pid)
raise
if status != 0:
error("%s failed with exit code %d\n" % (filename, status))
sys.exit(1)
def kill_all_processes(time_limit):
info("Killing all processes...")
try:
os.kill(-1, signal.SIGTERM)
except OSError:
pass
signal.alarm(time_limit)
try:
# Wait until no more child processes exist.
done = False
while not done:
try:
os.waitpid(-1, 0)
except OSError as e:
if e.errno == errno.ECHILD:
done = True done = True
else:
raise
except AlarmException:
warn("Not all processes have exited in time. Forcing them to exit.")
try:
os.kill(-1, signal.SIGKILL)
except OSError:
pass
finally:
signal.alarm(0)
# Runit has exited. Reset signal handlers. def run_startup_files():
print("*** Runit exited with code %s. Waiting for all services to shut down..." % status) # Run /etc/my_init.d/*
signal.signal(signal.SIGCHLD, signal.SIG_DFL) for name in listdir("/etc/my_init.d"):
signal.signal(signal.SIGTERM, signal.SIG_DFL) filename = "/etc/my_init.d/" + name
signal.siginterrupt(signal.SIGCHLD, False) if is_exe(filename):
signal.siginterrupt(signal.SIGTERM, False) info("Running %s..." % filename)
run_command_killable(filename)
# Wait at most 5 seconds for services to shut down. # Run /etc/rc.local.
import time if is_exe("/etc/rc.local"):
info("Running /etc/rc.local...")
run_command_killable("/etc/rc.local")
def shutdown(signum = None, frame = None): def start_runit():
global status info("Booting runit daemon...")
if status is not None: pid = os.spawnl(os.P_NOWAIT, "/usr/bin/runsvdir", "/usr/bin/runsvdir",
sys.exit(status) "-P", "/etc/service", "log: %s" % ('.' * 395))
info("Runit started as PID %d" % pid)
return pid
signal.signal(signal.SIGALRM, shutdown) def wait_for_runit_or_interrupt(pid):
signal.alarm(5) try:
done = False status = waitpid_reap_other_children(pid)
while not done: return (True, status)
except KeyboardInterrupt:
return (False, None)
def shutdown_runit_services():
debug("Begin shutting down runit services...")
os.system("/usr/bin/sv down /etc/service/*")
def wait_for_runit_services():
debug("Waiting for runit services to exit...")
done = False
while not done:
done = os.system("/usr/bin/sv status /etc/service/* | grep -q '^run:'") != 0 done = os.system("/usr/bin/sv status /etc/service/* | grep -q '^run:'") != 0
if not done: if not done:
time.sleep(0.5) time.sleep(0.1)
shutdown()
def main(args):
if not args.skip_startup_files:
run_startup_files()
runit_exited = False
exit_code = None
if not args.skip_runit:
runit_pid = start_runit()
try:
if len(args.main_command) == 0:
runit_exited, exit_code = wait_for_runit_or_interrupt(runit_pid)
if runit_exited:
info("Runit exited with code %d" % exit_code)
else:
info("Running %s..." % " ".join(args.main_command))
pid = os.spawnvp(os.P_NOWAIT, args.main_command[0], args.main_command)
try:
exit_code = waitpid_reap_other_children(pid)
info("%s exited with exit code %d." % (args.main_command[0], exit_code))
except KeyboardInterrupt:
stop_child_process(args.main_command[0], pid)
except BaseException as s:
warn("An error occurred. Aborting.")
stop_child_process(args.main_command[0], pid)
raise
sys.exit(exit_code)
finally:
if not args.skip_runit:
shutdown_runit_services()
if not runit_exited:
stop_child_process("runit daemon", runit_pid)
wait_for_runit_services()
# Parse options.
parser = argparse.ArgumentParser(description = 'Initialize the system.')
parser.add_argument('main_command', metavar = 'MAIN_COMMAND', type = str, nargs = '*',
help = 'The main command to run. (default: runit)')
parser.add_argument('--skip-startup-files', dest = 'skip_startup_files',
action = 'store_const', const = True, default = False,
help = 'Skip running /etc/my_init.d/* and /etc/rc.local')
parser.add_argument('--skip-runit', dest = 'skip_runit',
action = 'store_const', const = True, default = False,
help = 'Do not run runit services')
parser.add_argument('--no-kill-all-on-exit', dest = 'kill_all_on_exit',
action = 'store_const', const = False, default = True,
help = 'Don\'t kill all processes on the system upon exiting')
parser.add_argument('--quiet', dest = 'log_level',
action = 'store_const', const = LOG_LEVEL_WARN, default = LOG_LEVEL_INFO,
help = 'Only print warnings and errors')
args = parser.parse_args()
log_level = args.log_level
if args.skip_runit and len(args.main_command) == 0:
error("When --skip-runit is given, you must also pass a main command.")
sys.exit(1)
# Run main function.
signal.signal(signal.SIGTERM, lambda signum, frame: ignore_signals_and_raise_keyboard_interrupt('SIGTERM'))
signal.signal(signal.SIGINT, lambda signum, frame: ignore_signals_and_raise_keyboard_interrupt('SIGINT'))
signal.signal(signal.SIGALRM, lambda signum, frame: raise_alarm_exception())
try:
main(args)
except KeyboardInterrupt:
warn("Init system aborted.")
exit(2)
finally:
if args.kill_all_on_exit:
kill_all_processes(KILL_ALL_PROCESSES_TIMEOUT)

View File

@@ -14,7 +14,7 @@ $minimal_apt_get_install apt-transport-https
## Fix some issues with APT packages. ## Fix some issues with APT packages.
## See https://github.com/dotcloud/docker/issues/1024 ## See https://github.com/dotcloud/docker/issues/1024
dpkg-divert --local --rename --add /sbin/initctl dpkg-divert --local --rename --add /sbin/initctl
ln -s /bin/true /sbin/initctl ln -sf /bin/true /sbin/initctl
## Upgrade all packages. ## Upgrade all packages.
echo "initscripts hold" | dpkg --set-selections echo "initscripts hold" | dpkg --set-selections

View File

@@ -1,12 +1,26 @@
#!/bin/bash #!/usr/bin/python2
set -e import sys, os, pwd
user="$1" if len(sys.argv) < 3:
shift sys.stderr.write("Usage: /sbin/setuser USERNAME COMMAND [args..]\n")
sys.exit(1)
if [[ "$user" == "root" ]]; then def abort(message):
export HOME=/root sys.stderr.write("setuser: %s\n" % message)
else sys.exit(1)
export HOME=/home/$user
fi username = sys.argv[1]
exec chpst -u "$user" "$@" try:
user = pwd.getpwnam(username)
except KeyError:
abort("user %s not found" % username)
os.initgroups(username, user.pw_gid)
os.setgid(user.pw_gid)
os.setuid(user.pw_uid)
os.environ['USER'] = username
os.environ['HOME'] = user.pw_dir
os.environ['UID'] = str(user.pw_uid)
try:
os.execvp(sys.argv[2], sys.argv[2:])
except OSError as e:
abort("cannot execute %s: %s" % (sys.argv[2], str(e)))

View File

@@ -5,6 +5,7 @@ set -x
## Install init process. ## Install init process.
cp /build/my_init /sbin/ cp /build/my_init /sbin/
mkdir -p /etc/my_init.d
## Install runit. ## Install runit.
$minimal_apt_get_install runit $minimal_apt_get_install runit
@@ -13,6 +14,7 @@ $minimal_apt_get_install runit
$minimal_apt_get_install syslog-ng-core $minimal_apt_get_install syslog-ng-core
mkdir /etc/service/syslog-ng mkdir /etc/service/syslog-ng
cp /build/runit/syslog-ng /etc/service/syslog-ng/run cp /build/runit/syslog-ng /etc/service/syslog-ng/run
mkdir -p /var/lib/syslog-ng
## Install the SSH server. ## Install the SSH server.
$minimal_apt_get_install openssh-server $minimal_apt_get_install openssh-server
@@ -20,12 +22,16 @@ mkdir /var/run/sshd
mkdir /etc/service/sshd mkdir /etc/service/sshd
cp /build/runit/sshd /etc/service/sshd/run cp /build/runit/sshd /etc/service/sshd/run
cp /build/config/sshd_config /etc/ssh/sshd_config cp /build/config/sshd_config /etc/ssh/sshd_config
cp /build/00_regen_ssh_host_keys.sh /etc/my_init.d/
## Install default SSH key for root and app. ## Install default SSH key for root and app.
mkdir -p /root/.ssh mkdir -p /root/.ssh
chmod 700 /root/.ssh chmod 700 /root/.ssh
chown root:root /root/.ssh chown root:root /root/.ssh
cat /build/insecure_key.pub > /root/.ssh/authorized_keys cp /build/insecure_key.pub /etc/insecure_key.pub
chmod 644 /etc/insecure_key.pub
chown root:root /etc/insecure_key.pub
cp /build/enable_insecure_key /usr/sbin/
## Install cron daemon. ## Install cron daemon.
$minimal_apt_get_install cron $minimal_apt_get_install cron

42
test/runner.sh Normal file
View File

@@ -0,0 +1,42 @@
#!/bin/bash
set -e
function abort()
{
echo "$@"
exit 1
}
function cleanup()
{
echo " --> Stopping container"
docker stop $ID >/dev/null
docker rm $ID >/dev/null
docker rmi baseimage_test >/dev/null 2>/dev/null
}
PWD=`pwd`
echo " --> Preparing container"
ID=`docker run -d $NAME:$VERSION enable_insecure_key`
docker wait $ID >/dev/null
docker commit $ID baseimage_test >/dev/null
docker rm $ID >/dev/null
echo " --> Starting container"
ID=`docker run -d -v $PWD/test:/test baseimage_test /sbin/my_init`
sleep 1
echo " --> Obtaining IP"
IP=`docker inspect $ID | grep IPAddress | sed -e 's/.*: "//; s/".*//'`
if [[ "$IP" = "" ]]; then
abort "Unable to obtain container IP"
fi
trap cleanup EXIT
echo " --> Logging into container and running tests"
chmod 600 image/insecure_key
sleep 1 # Give container some more time to start up.
ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -i image/insecure_key root@$IP \
/bin/bash /test/test.sh

22
test/test.sh Normal file
View File

@@ -0,0 +1,22 @@
#!/bin/bash
set -o pipefail
function ok()
{
echo " OK"
}
function fail()
{
echo " FAIL"
exit 1
}
echo "Checking whether all services are running..."
services=`sv status /etc/service/*`
status=$?
if [[ "$status" != 0 || "$services" = "" || "$services" =~ down ]]; then
fail
else
ok
fi