DockTartar

• Introduction
• Getting started
  • Installation
  • Quickstart
  • Environment Variables
• Maintenance
  • Upgrading
  • Shell Access
• Change history
• Contributing
• Issues

Introduction

Docktartar will recursively tar a directory to another location. It has been designed to stop running docker containers before doing the backup and restart them after the archival process.

Some Features:

• Multi-Core Compression with pigz
• CRON daemon to schedule the backup job
• SMB Client to backup to a network share
• Temp-Directory to build the archive locally (eg SSD), restart the containers and move the archive afterwards
• Mail notifications with ssmtp
• Full configuration with environment variables
• Chose which containers to stop and restart

You can provide a temp-directory for faster archival, afterwards the script will move the archive wherever you want. This is useful in cases where you want to store your backup on a remote server (you should really do this!). The workflow in this case is:

1. Stop Containers
2. Build the archive in the /backupTmp directory
3. Start containers
4. move the archive from /backupTmp to /targetTmp
5. Chown the archive

Getting started

Installation

Automated builds of the image are available on Dockerhub and is the recommended method of installation.

docker pull gmentsik/docktartar

Alternatively you can build the image yourself.

docker build -t gmentsik/docktartar github.com/gmentsik/docktartar

Quickstart

You can use the sample docker-compose.yml file to start the container using Docker Compose*

Or start Docktartar using:

docker run -d --name docktartar \
              --restart=always \
              --volume /srv/docker:/backupSource \
              --volume /var/backups/docker:/backupTarget  \
              --volume /var/run/docker.sock:/var/run/docker.sock \
              --volume /var/lib/docker:/var/lib/docker \
      gmentsik/docktartar

Environment Variables

Variable	Default Value	Description	Examples
CRON	"0 0 * * *"	(=Midnight) When the script should start in cron format. Check cron-generator	"0 30 * * *" , "0 0 */3 * *"
TIMEZONE	"Europe/Vienna"	Sets the timezone of the container.	'Asia/Tokyo','America/Los_Angeles'
TAR_OWNER_USERID	0	Sets the Owner of the archive. 0 = root	enter id for all users on your system
TAR_OWNER_GROUPID	0	Sets the Group-Owner of the archive. 0 = root	enter id for all users on your system
TAG	"docker"	Sets filename tag.[timestamp].tar.gz	docker-backup
STOP_CONTAINERS	"all"	The containers to stop. Either Name, Id or all. nginx mysql all will stop nginx then mysql and then all others.	mysql all, nginx mysql, all
START_CONTAINERS	"all"	The containers to start. Either Name, Id or all. nginx mysql all will start nginx then mysql and then all others.	mysql all, nginx mysql, all
INCREMENTAL	"true"	Generates incremental backups	true or false
SMB	"false"	Enables Samba integration	true or false
SMB_USER	""	Username of the samba user	username
SMB_PASSWORD	""	Password of the samba user	pass
SMB_SMB_PATH	""	IP+Path of the Samba Network Share	192.162.4.10/shares/backups
EMAIL_HOST_PORT	""	Host and port of your e-mail server/smarthost The format is host.tld:port	mail.company.com:587
EMAIL_USER	""	Username for authentication on your mail server	web58p4
EMAIL_PASS	""	Password for authentication on your mail server	secretpassword
EMAIL_USE_STARTTLS	"NO"	use starttls, YES or NO	YES or NO
EMAIL_FROM	"Docktartar"	The name that is displayed in the from field	Docktartar
EMAIL_FROM_ADRESS	""	The e-mail adress that is displayed in the from field	[email protected]
EMAIL_SUBJECT	"Docktartar"	The subject of the message	Backupjob
EMAIL_TO	""	The E-Mail adress where the emails should be send	[email protected]
TEMP_DIR	"NO"	If set to YES, the archive is built in /backupTmp and then moved to /backupTarget, after the all containers restarted	YES or NO

Samba Share and Permissions

In order to run this with samba share as the backup target, you have to either run the container with privileged: true or add cap_add: SYS_ADMIN

Volumes

Container Volume	Description
/backupSource	The contents of this folder will be archived in a tar-archive.
/backupTarget	The tar-archive will be put in this directory. If you use a Network share, do not mount this!
/var/run/docker.sock	Has to be mapped in ordner to be able to stop and start containers.
/var/lib/docker	Has to be mapped in ordner to be able to stop and start containers.

Maintenance

Test Mail settings

There is a test script in the root folder called test-mail.sh which can be used to test the email settings.

docker exec -it docktartar /root/test-mail.sh

Upgrading

To upgrade to newer releases:

1. Download the updated Docker image:

docker pull gmentsik/docktartar

2. Stop the currently running image:

docker stop docktartar

3. Remove the stopped container

docker rm -v docktartar

4. Start the updated image

docker run -name docktartar -d [OPTIONS] gmentsik/docktartar

Shell Access

For debugging and maintenance purposes you may want access the containers shell. If you are using Docker version 1.3.0 or higher you can access a running containers shell by starting bash using docker exec:

docker exec -it docktartar bash

Contributing

If you find this image useful here's how you can help:

• Send a pull request with your awesome features and bug fixes
• Help users resolve their issues.

Issues

Before reporting your issue please try updating Docker to the latest version and check if it resolves the issue. Refer to the Docker installation guide for instructions.

SELinux users should try disabling SELinux using the command setenforce 0 to see if it resolves the issue.

If the above recommendations do not help then report your issue along with the following information:

• Output of the docker version and docker info commands
• The docker run command or docker-compose.yml used to start the image. Mask out the sensitive bits.
• Please state if you are using Boot2Docker, VirtualBox, etc.