Docker implemented in 100 lines of bash.

• Prerequisites
• Example Usage
• Functionality: Currently Implemented
• Functionality: Not Yet Implemented
• License

The following packages are needed to run bocker.

• btrfs-progs
• iproute2
• iptables
• util-linux >= 2.25.2

Because most distributions do not ship a new enough version of util-linux you will probably need grab the sources from here and compile it yourself.

Additionally your system will need to be configured with the following.

• A btrfs filesystem mounted under /var/bocker
• A network bridge called bridge0 and an IP of 10.0.0.1/24
• IP forwarding enabled in /proc/sys/net/ipv4/ip_forward
• A firewall routing traffic from bridge0 to a physical interface.
• A base-image which contains the filesystem to seed your container with.

For ease of use a Vagrantfile is included which will build the needed environment.

Even if you meet the above prerequisites you probably still want to run bocker in a virtual machine. Bocker runs as root and among other things needs to make changes to your network interfaces, routing table, and firewall rules. I can make no guarantees that it wont trash your system.

$ bocker init base-image/
Created: img_84632

$ bocker images
IMAGE_ID
img_84632

$ bocker run img_84632 uname -sro
Linux 3.10.0-123.20.1.el7.x86_64 GNU/Linux

$ bocker ps
CONTAINER_ID       COMMAND
ps_12277           uname -sro

$ bocker logs ps_12277
Linux 3.10.0-123.20.1.el7.x86_64 GNU/Linux

$ bocker rm ps_12277
Removed: ps_12277

$ bocker run img_84632 which wget
which: no wget in (/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin)

$ bocker run img_84632 yum install -y wget
Installing : wget-1.14-10.el7_0.1.x86_64                                  1/1
Verifying  : wget-1.14-10.el7_0.1.x86_64                                  1/1
Installed  : wget.x86_64 0:1.14-10.el7_0.1
Complete!

$ bocker ps
CONTAINER_ID       COMMAND
ps_14099           which wget
ps_43377           yum install -y wget

$bocker commit ps_43377 img_84632
Removed: img_84632
Created: img_84632

$ bocker run img_84632 which wget
/usr/bin/wget

$ bocker rm ps_14099
Removed: ps_14099

$ bocker rm ps_43377
Removed: ps_43377

$ bocker rm ps_95942
Removed: ps_95942

$ bocker rm img_84632
Removed: img_84632

• docker build †
• docker images
• docker ps
• docker run
• docker logs
• docker commit
• docker rm / docker rmi
• Networking

† bocker init provides a very limited implemetation of docker build

• Port Forwarding
• Data Volumes
• Data Volume Containers

Copyright (C) 2015 Peter Wilmott

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see https://www.gnu.org/licenses/.