Loading initial data into a Redis Docker container - redis

I'm trying to create a Redis Docker image, based on the redis:3. However, I need to load a small amount of test data into the image (it is used for testing, both on developer machines and on the CI server).
My initial attempt looks like:
FROM redis:3.0.3
MAINTAINER Howard M. Lewis Ship
RUN redis-cli sadd production-stores 5555
But this fails with the error:
Step 2 : RUN redis-cli sadd production-stores 5555
---> Running in 60fb98c133c0
Could not connect to Redis at 127.0.0.1:6379: Connection refused
The command '/bin/sh -c redis-cli sadd production-stores 5555' returned a non-zero code: 1
I'm wondering if there's a trick that allows me, in a Docker file, to connect to the server started via the CMD/ENTRYPOINT of the Dockerfile. As I'm guessing right now, the RUN occurs before the command is started.
Alternately, is there a Redis command or trick that would allow me to load some data into its database.
I suspect one approach would be to mount the Redis' data directory in a volume exposed to the Docker host; this is not ideal as
I would need an extra non-Dockerfile command to load the data
The loaded data would not be shared in the image, which is to be used by others on my team
I'm on OS X and am using docker-machine, so the volumes get trickier

The error tells Redis service is not started before you run redis-cli.
Add a new line to start it first. Let me know if this can fix your issue or not.
FROM redis:3.0.3
MAINTAINER Howard M. Lewis Ship
RUN /usr/sbin/redis-server /etc/redis.conf
RUN redis-cli sadd production-stores 5555
Updates:
Review the official redis image, it has given the way to use redis-cli
# via redis-cli
$ docker run -it --link some-redis:redis --rm redis sh -c 'exec redis-cli -h "$REDIS_PORT_6379_TCP_ADDR" -p "$REDIS_PORT_6379_TCP_PORT"'
So I test the image and make it run as below:
# start redis container
$ docker run --name some-redis -d redis
# link redis container and run redis-cli command
$ docker run -it --link some-redis:redis --rm redis redis-cli -h redis
redis:6379> PING
PONG
redis:6379> exit
# Add the specified members to the set stored at key
$ docker run -it --link some-redis:redis --rm redis redis-cli -h redis sadd production-stores 5555
(integer) 1
$

Related

Redis server on diffrent node using docker on ubuntu 20

i want to setup redis cluster on 3 diffrent nodes using docker..can any one suggest the commands or some documents for setup?
i am finding the documents for single node but i want it for multiple nodes
any help would be appriciated
Thank you!
so i followed these steps to setup redis cluster on 3 diffrent servers.
add entries in nano /etc/hosts file on all the nodes 3 nodes
ip1 hostname1
ip2 hostname2
ip3 hostname3
then save and exit
on node1
docker run --name redis-node-1 --hostname hostname1 --net test -p 6379:6379 -p 16379:16379 -d redis redis-server --cluster-enabled yes --cluster-config-file nodes.conf --cluster-node-timeout 5000
on node2
docker run --name redis-node-2 --hostname hostname2 --net test -p 6379:6379 -p 16379:16379 -d redis redis-server --cluster-enabled yes --cluster-config-file nodes.conf --cluster-node-timeout 5000
on node3
docker run --name redis-node-3 --hostname hostname3 --net test -p 6379:6379 -p 16379:16379 -d redis redis-server --cluster-enabled yes --cluster-config-file nodes.conf --cluster-node-timeout 5000
now once all 3 containers are up run the below command on any node.i am running it on 1st node.
docker exec -it redis-node-1 redis-cli --cluster create ip1:6379 ip2:6379 ip3:6379 --cluster-replicas 0
after the setup is complete verify it with below command
docker exec -it redis-node-1 redis-cli cluster info
This worked for me ..Thank you!

redis container how to load lua script from host

I am trying to execute a lua script against a redis instance running in a container. The code is very simple 2 liner example.
local foo = redis.call("ping")
return foo
As this file is on the host machine, how do i get it to execute inside docker exec ? Or should I install redis-cli locally to test it?
I think I understood what you want. You have a Lua script on your docker host that you want to load into Redis running inside a docker container without needing redis-cli on the host.
So, start the official Redis in a container as a daemon:
docker run --name some-redis -d redis
Now, assuming your script is on the host in a file called script.lua, you want to load that into dockerised Redis:
docker exec -i some-redis redis-cli -x script load < script.lua
That will return a SHA sum - I got 93126620988a563ac9dd347d02a9cdbbbeaee3c1 - and you can then run the script with:
docker exec -i some-redis redis-cli EVALSHA 93126620988a563ac9dd347d02a9cdbbbeaee3c1 0
PONG
If you want to automate the capture of the SHA sum and its subsequent use:
sha=$(docker exec -i some-redis redis-cli -x script load < script.lua)
Then:
docker exec -i some-redis redis-cli EVALSHA $sha 0
PONG

redis: Create cluster with redis-cli non interactively

When trying to create a cluster with redis-cli as follows
redis-cli --cluster create
a prompt comes up asking for configuration confirmation?
Is there a way to script this (preferably in ansible) and run it non-interactively?
I am aware of this topic however it addresses data manipulation which is not the scope of this question.
--cluster-yes is the correct option!
EDIT:
The answer of Leonardo Oliveira rightfully points out that the option --cluster-yes will avoid the prompt. For example:
redis-cli --cluster create host1:6379 host2:6379 host3:6379 --cluster-yes
As of the current Redis version (5.0.5) there doesn't seem to be a flag under --cluster that can silence or auto-answer the interactive question:
$ redis-cli --cluster help
Cluster Manager Commands:
create host1:port1 ... hostN:portN
--cluster-replicas <arg>
check host:port
--cluster-search-multiple-owners
info host:port
fix host:port
--cluster-search-multiple-owners
reshard host:port
--cluster-from <arg>
--cluster-to <arg>
--cluster-slots <arg>
--cluster-yes
--cluster-timeout <arg>
--cluster-pipeline <arg>
--cluster-replace
rebalance host:port
--cluster-weight <node1=w1...nodeN=wN>
--cluster-use-empty-masters
--cluster-timeout <arg>
--cluster-simulate
--cluster-pipeline <arg>
--cluster-threshold <arg>
--cluster-replace
add-node new_host:new_port existing_host:existing_port
--cluster-slave
--cluster-master-id <arg>
del-node host:port node_id
call host:port command arg arg .. arg
set-timeout host:port milliseconds
import host:port
--cluster-from <arg>
--cluster-copy
--cluster-replace
help
By using echo you can execute the command and auto-answer the prompt:
echo "yes" | redis-cli --cluster create host1:6379 host2:6379 host3:6379
The default Ansible Redis module only supports a few commands and not --cluster so you would have to create your own logic with command/shell tasks:
- name: Create cluster
shell: echo "yes" | redis-cli --cluster create host1:6379 host2:6379 host3:6379
run_once: true
when: not cluster_setup_done
Well, I don't know about the ansible part. But Redis official site does provide a way to create cluster with script in a little interactive-mode.
Creating a Redis Cluster using the create-cluster script (Please refer docs for more details)
If you don't want to create a Redis Cluster by configuring and executing individual instances manually as explained above, there is a much simpler system (but you'll not learn the same amount of operational details).
Just check utils/create-cluster directory in the Redis distribution. There is a script called create-cluster inside (same name as the directory it is contained into), it's a simple bash script. In order to start a 6 nodes cluster with 3 masters and 3 slaves just type the following commands:
create-cluster start
create-cluster create
Reply to yes in step 2 when the redis-cli utility wants you to accept the cluster layout.
You can now interact with the cluster, the first node will start at port 30001 by default. When you are done, stop the cluster with:
create-cluster stop
Please read the README inside this directory for more information on how to run the script.
You can try implementing this if it helps you in any way!
Cheers :)

How to pass securely SSH Keys to Docker Build?

I want to create a Docker image for devs that reproduces our production servers. Those servers are configured by Ansible.
My idea is to run an ansible-pull to apply all the configuration inside the container. The problem is that I need the SSH key to pull the playbook, but I don't want to share the SSH key on the Docker image.
So, there is a way to have the SSH keys on build time without having them on run time?
Nice question. The simple way to do it is by removing the SSH keys after the Ansible stuff in the build - but because Docker stores images as layers, someone could still find the old layer with the keys in it.
If you build this Dockerfile:
FROM ubuntu
COPY ansible-ssh-key.rsa /key.rsa
RUN [ansible stuff]
RUN rm /key.rsa
The final image will have all your Ansible state and the SSH key will be gone but someone could easily run docker history to look at all the image layers, and just start a container from an intermediate layer before the key was deleted, and grab the key.
The trick would be to do something like this and then use Jason Wilder's docker-squash tool to squash the final image. In the squashed image the intermediate layer is gone and there's no way to get at the deleted key.
I'd setup some local file serving facility available only in your build environment.
E.g. start lighttpd on your build host to serve your pem-files only to local clients.
And in your Dockerfile do add/pull/cleanup in a single run:
RUN curl -sO http://build-host:8888/key.pem && ansible-pull -U myrepo && rm -rf key.pem
In this case it should be done in a single layer, so there should be no trace of key.pem left after layer commit.
This is another solution by using this repo, dockito/vault,
Secret store to be used on Docker image building.
I create a service dockito/vault and Ubuntu image where I attach my private key to the volume and run it as a process using,
docker run -it -v ~/.ssh:/vault/.ssh ubuntu /bin/bash -c "echo mysupersecret > /vault/.ssh/key"
docker run -d -p 14242:3000 -v ~/.ssh:/vault/.ssh dockito/vault
And, here is my Dockerfile
FROM ubuntu:14.04
RUN apt-get update -y && \
apt-get install -y curl && \
curl -L $(ip route|awk '/default/{print $3}'):14242/ONVAULT >
/usr/local
/bin/ONVAULT && \
chmod +x /usr/local/bin/ONVAULT
ENV REV_BREAK_CACHE=1
RUN ONVAULT echo ENV: && env && echo TOKEN ENV && echo $TOKEN
RUN ONVAULT ls -lha ~/.ssh/
RUN ONVAULT cat ~/.ssh/key
You can use the alpine linux to reduce final build size, and built the image as,
docker build -f Dockerfile -t mohan08p/VaultTest .
And, you are done. You can inspect the image. Secrets has not stored inside the image as its empty.
docker run -it mohan08p/VaultTest ls /root/.ssh
This is good technique to pass the .ssh at the build time. Only disadvantage is I need to keep additional Vault service running.
You could mount the SSH Keys into the Container on runtime.
docker run -v /path/to/ssh/key:/path/to/key/in/container image command

How can I backup a Docker-container with its data-volumes?

I've been using this Docker-image tutum/wordpress to demonstrate a Wordpress website. Recently I found out that the image uses volumes for the MySQL-data.
So the problem is this: If I want to backup and restore the container I can try to commit an image, and then later delete the container, and create a new container from the committed image. But if I do that the volume gets deleted and all my data is gone.
There must be some simple way to backup my container plus its volume-data but I can't find it anywhere.
if I want to revert the container I can try to commit an image, and then later delete the container, and create a new container from the committed image. But if I do that the volume gets deleted and all my data is gone
As the docker user guide explains, data volumes are meant to persist data outside of a container filesystem. This also eases the sharing of data between multiple containers.
While Docker will never delete data in volumes (unless you delete the associated container with docker rm -v), volumes that are not referenced by any docker container are called dangling volumes. Those dangling volumes are difficult to get rid of and difficult to access.
This means that as soon as the last container using a volume is deleted, the data volume becomes dangling and its content difficult to access.
In order to prevent those dangling volumes, the trick is to create an additional docker container using the data volume you want to persist so that there will always be at least that docker container referencing the volume. This way you can delete the docker container running the wordpress app without losing the ease of access to that data volume content.
Such containers are called data volume containers.
There must be some simple way to back up my container plus volume data but I can't find it anywhere.
back up docker images
To back up docker images, use the docker save command that will produce a tar archive that can be used later on to create a new docker image with the docker load command.
back up docker containers
You can back up a docker container by different means
by committing a new docker image based on the docker container current state using the docker commit command
by exporting the docker container file system as a tar archive using the docker export command. You can later on create a new docker image from that tar archive with the docker import command.
Be aware that those commands will only back up the docker container layered file system. This excludes the data volumes.
back up docker data volumes
To back up a data volume you can run a new container using the volume you want to back up and executing the tar command to produce an archive of the volume content as described in the docker user guide.
In your particular case, the data volume is used to store the data for a MySQL server. So if you want to export a tar archive for this volume, you will need to stop the MySQL server first. To do so you will have to stop the wordpress container.
back up the MySQL data
An other way is to remotely connect to the MySQL server to produce a database dump with the mysqldump command. However in order for this to work, your MySQL server must be configured to accept remote connections and also have a user who is allowed to connect remotely. This might not be the case with the wordpress docker image you are using.
Edit
Docker recently introduced Docker volume plugins which allow to delegate the handling of volumes to plugins implemented by vendors.
The docker run command has a new behavior for the -v option. It is now possible to pass it a volume name. Volumes created in that way are named and easy to reference later on, easing the issues with dangling volumes.
Edit 2
Docker introduced the docker volume prune command to delete all dangling volumes easily.
UPDATE 2
Raw single volume backup bash script:
#!/bin/bash
# This script allows you to backup a single volume from a container
# Data in given volume is saved in the current directory in a tar archive.
CONTAINER_NAME=$1
VOLUME_PATH=$2
usage() {
echo "Usage: $0 [container name] [volume path]"
exit 1
}
if [ -z $CONTAINER_NAME ]
then
echo "Error: missing container name parameter."
usage
fi
if [ -z $VOLUME_PATH ]
then
echo "Error: missing volume path parameter."
usage
fi
sudo docker run --rm --volumes-from $CONTAINER_NAME -v $(pwd):/backup busybox tar cvf /backup/backup.tar $VOLUME_PATH
Raw single volume restore bash script:
#!/bin/bash
# This script allows you to restore a single volume from a container
# Data in restored in volume with same backupped path
NEW_CONTAINER_NAME=$1
usage() {
echo "Usage: $0 [container name]"
exit 1
}
if [ -z $NEW_CONTAINER_NAME ]
then
echo "Error: missing container name parameter."
usage
fi
sudo docker run --rm --volumes-from $NEW_CONTAINER_NAME -v $(pwd):/backup busybox tar xvf /backup/backup.tar
Usage can be like this:
$ volume_backup.sh old_container /srv/www
$ sudo docker stop old_container && sudo docker rm old_container
$ sudo docker run -d --name new_container myrepo/new_container
$ volume_restore.sh new_container
Assumptions are: backup file is named backup.tar, it resides in the same directory as backup and restore script, volume name is the same between containers.
UPDATE
It seems to me that backupping volumes from containers is not different from backupping volumes from data containers.
Volumes are nothing else than paths linked to a container so the process is the same.
I don't know if docker-backup works also for same container volumes but you can use:
sudo docker run --rm --volumes-from yourcontainer -v $(pwd):/backup busybox tar cvf /backup/backup.tar /data
and:
sudo docker run --rm --volumes-from yournewcontainer -v $(pwd):/backup busybox tar xvf /backup/backup.tar
END UPDATE
There is this nice tool available which lets you backup and restore docker volumes containers:
https://github.com/discordianfish/docker-backup
if you have a container linked to some container volumes like this:
$ docker run --volumes-from=my-data-container --name my-server ...
you can backup all the volumes like this:
$ docker-backup store my-server-backup.tar my-server
and restore like this:
$ docker-backup restore my-server-backup.tar
Or you can follow the official way:
How to port data-only volumes from one host to another?
If your project uses docker-compose, here is an approach for backing up and restoring your volumes.
docker-compose.yml
Basically you add db-backup and db-restore services to your docker-compose.yml file, and adapt it for the name of your volume. My volume is named dbdata in this example.
version: "3"
services:
db:
image: percona:5.7
volumes:
- dbdata:/var/lib/mysql
db-backup:
image: alpine
tty: false
environment:
- TARGET=dbdata
volumes:
- ./backup:/backup
- dbdata:/volume
command: sh -c "tar -cjf /backup/$${TARGET}.tar.bz2 -C /volume ./"
db-restore:
image: alpine
environment:
- SOURCE=dbdata
volumes:
- ./backup:/backup
- dbdata:/volume
command: sh -c "rm -rf /volume/* /volume/..?* /volume/.[!.]* ; tar -C /volume/ -xjf /backup/$${SOURCE}.tar.bz2"
Avoid corruption
For data consistency, stop your db container before backing up or restoring
docker-compose stop db
Backing up
To back up to the default destination (backup/dbdata.tar.bz2):
docker-compose run --rm db-backup
Or, if you want to specify an alternate target name, do:
docker-compose run --rm -e TARGET=mybackup db-backup
Restoring
To restore from backup/dbdata.tar.bz2, do:
docker-compose run --rm db-restore
Or restore from a specific file using:
docker-compose run --rm -e SOURCE=mybackup db-restore
I adapted commands from https://loomchild.net/2017/03/26/backup-restore-docker-named-volumes/ to create this approach.
If you only need to backup mounted volumes you can just copy folders from your Dockerhost.
Note: If you are on Ubuntu, Dockerhost is your local machine. If you are on Mac, Dockerhost is your virtual machine.
On Ubuntu
You can find all folders with volumes here: /var/lib/docker/volumes/ so you can copy them and archive wherever you want.
On MAC
It's not so easy as on Ubuntu. You need to copy files from VM.
Here is a script of how to copy all folders with volumes from virtual machine (where Docker server is running) to your local machine. We assume that your docker-machine VM named default.
docker-machine ssh default sudo cp -v -R /var/lib/docker/volumes/ /home/docker/volumes
docker-machine ssh default sudo chmod -R 777 /home/docker/volumes
docker-machine scp -R default:/home/docker/volumes ./backup_volumes
docker-machine ssh default sudo rm -r /home/docker/volumes
It is going to create a folder ./backup_volumes in your current directory and copy all volumes to this folder.
Here is a script of how to copy all saved volumes from your local directory (./backup_volumes) to Dockerhost machine
docker-machine scp -r ./backup_volumes default:/home/docker
docker-machine ssh default sudo mv -f /home/docker/backup_volumes /home/docker/volumes
docker-machine ssh default sudo chmod -R 777 /home/docker/volumes
docker-machine ssh default sudo cp -v -R /home/docker/volumes /var/lib/docker/
docker-machine ssh default sudo rm -r /home/docker/volumes
Now you can check if it works by:
docker volume ls
Let's say your volume name is data_volume. You can use the following commands to backup and restore the volume to and from a docker image named data_image:
To backup:
docker run --rm --mount source=data_volume,destination=/data alpine tar -c -f- data | docker run -i --name data_container alpine tar -x -f-
docker container commit data_container data_image
docker rm data_container
To restore:
docker run --rm data_image tar -c -f- data | docker run -i --rm --mount source=data_volume,destination=/data alpine tar -x -f-
I know this is old, but I realize that there isnt a well documented solution to pushing a data container (as backup) to docker hub. I just published a short example on how doing so at
https://dzone.com/articles/docker-backup-your-data-volumes-to-docker-hub
Following is the bottom line
The docker tutorial suggest you can backup and restore the data volume locally. We are going to use this technique, add a few more lines to get this backup pushed into docker hub for easy future restoration to any location we desire. So, lets get started. These are the steps to follow:
Backup the data volume from the data container named data-container-to-backup
docker run --rm --volumes-from data-container-backup --name tmp-backup -v $(pwd):/backup ubuntu tar cvf /backup/backup.tar /folderToBackup
Expand this tar file into a new container so we can commit it as part of its image
docker run -d -v $(pwd):/backup --name data-backup ubuntu /bin/sh -c "cd / && tar xvf /backup/backup.tar"
Commit and push the image with a desired tag ($VERSION)
docker commit data-backup repo/data-backup:$VERSION
docker push repo/data-backup:$VERSION
Finally, lets clean up
docker rm data-backup
docker rmi $(docker images -f "dangling=true" -q)
Now we have an image named data-backup in our repo that is simply a filesystem with the backup files and folders. In order use this image (aka restore from backup), we do the following:
Run the data container with the data-backup image
run -v /folderToBackup --entrypoint "bin/sh" --name data-container repo/data-backup:${VERSION}
Run your whatEver image with volumes from the data-conainter
docker run --volumes-from=data-container repo/whatEver
Thats it.
I was surprised there is no documentation for this work around. I hope someone find this helpful. I know it took me a while to think about this.
The following command will run tar in a container with all named data volumes mounted, and redirect the output into a file:
docker run --rm `docker volume list -q | egrep -v '^.{64}$' | awk '{print "-v " $1 ":/mnt/" $1}'` alpine tar -C /mnt -cj . > data-volumes.tar.bz2
Make sure to test the resulting archive in case something went wrong:
tar -tjf data-volumes.tar.bz2
If you just need a simple backup to an archive, you can try my little utility: https://github.com/loomchild/volume-backup
Example
Backup:
docker run -v some_volume:/volume -v /tmp:/backup --rm loomchild/volume-backup backup archive1
will archive volume named some_volume to /tmp/archive1.tar.bz2 archive file
Restore:
docker run -v some_volume:/volume -v /tmp:/backup --rm loomchild/volume-backup restore archive1
will wipe and restore volume named some_volume from /tmp/archive1.tar.bz2 archive file.
More info: https://medium.com/#loomchild/backup-restore-docker-named-volumes-350397b8e362
I have created a tool to orchestrate and launch backup of data and mysql containers, simply called docker-backup. There is even a ready-to-use image on the docker hub.
It's mainly written in Bash as it is mainly orchestration. It uses duplicity for the actual backup engine. You can currently backup to FTP(S) and Amazon S3.
The configuration is quite simple: write a config file in YAML describing what to backup and where, and here you go!
For data containers, it automatically mount the volumes shared by your container to backup and process it. For mysql containers, it links them and execute a mysqldump bundled with your container and process the result.
I wrote it because I use Docker-Cloud which is not up-to-date with recent docker-engine releases and because I wanted to embrace the Docker way by not including any process of backup inside my application containers.
If you want a complete backup, you will need to perform a few steps:
Commit the container to an image
Save the image
Backup the container's volume by creating a tar file of the volume's mount point in the container.
Repeat steps 1-3 for the database container as well.
Note that doing just a Docker commit of the container to an image does NOT include volumes attached to the container (ref: Docker commit documentation).
"The commit operation will not include any data contained in volumes mounted inside the container."
We can use an image to back up all our volumes. I write a script to help backup and restore. furthermore, I save the data to a tar file compression to save all data on a local disc. I use this script to save my Postgres and Cassandra volume databases at the same image. for example, if we have a pg_data for Postgres and cassandra_data for Cassandra database we can call the following script twice one with pg_data argument and then cassandra_data argument for Cassandra
backup script:
#! /bin/bash
GENERATE_IMAGE="data_image"
TEMPRORY_CONTAINER_NAME="data_container"
VOLUME_TO_BACKUP=${1}
RANDOM=$(head -200 /dev/urandom | cksum | cut -f1 -d " ")
if docker images | grep -q ${GENERATE_IMAGE}; then
docker run --rm --mount source=${VOLUME_TO_BACKUP},destination=/${VOLUME_TO_BACKUP} ${GENERATE_IMAGE} tar -c -f- ${VOLUME_TO_BACKUP} | docker run -i --name ${TEMPRORY_CONTAINER_NAME} ${GENERATE_IMAGE} tar -x -f-
else
docker run --rm --mount source=${VOLUME_TO_BACKUP},destination=/${VOLUME_TO_BACKUP} alpine tar -c -f- ${VOLUME_TO_BACKUP} | docker run -i --name ${TEMPRORY_CONTAINER_NAME} alpine tar -x -f-
fi
docker container commit ${TEMPRORY_CONTAINER_NAME} ${GENERATE_IMAGE}
docker rm ${TEMPRORY_CONTAINER_NAME}
if [ -f "$(pwd)/backup/${VOLUME_TO_BACKUP}.tar" ]; then
docker run --rm -v $(pwd)/backup:/backup ${GENERATE_IMAGE} tar cvf /backup/${VOLUME_TO_BACKUP}_${RANDOM}.tar /${VOLUME_TO_BACKUP}
else
docker run --rm -v $(pwd)/backup:/backup ${GENERATE_IMAGE} tar cvf /backup/${VOLUME_TO_BACKUP}.tar /${VOLUME_TO_BACKUP}
fi
example:
./backup.sh cassandra_data
./backup.sh pg_data
Restore script:
#! /bin/bash
GENERATE_IMAGE="data_image"
TEMPRORY_CONTAINER_NAME="data_container"
VOLUME_TO_RESTORE=${1}
docker run --rm ${GENERATE_IMAGE} tar -c -f- ${VOLUME_TO_RESTORE} | docker run -i --rm --mount source=${VOLUME_TO_RESTORE},destination=/${VOLUME_TO_RESTORE} alpine tar -x -f-
example:
./restore.sh cassandra_data
./restore.sh pg_data
The problem: You want to backup you image container WITH the data volumes in it but this option is Not out off the box, The straight forward and trivial way would be copy the volumes path and backup the docker image 'reload it and and link it both together. but this solution seems to be clumsy and not sustainable and maintainable - You would need to create a cron job that would make this flow each time.
Solution: Using dockup - Docker image to backup your Docker container volumes and upload it to s3 (Docker + Backup = dockup) . dockup will use your AWS credentials to create a new bucket with name as per the environment variable ,gets the configured volumes and will be tarballed, gzipped, time-stamped and uploaded to the S3 bucket.
Steps:
configure the docker-compose.yml and attach the env.txt configuration file to it, The data should be uploaded to a dedicated secured s3 bucket and ready to be reloaded on DRP executions. in order to verify which volumes path to configure run docker inspect <service-name> and locate the volumes :
"Volumes": {
"/etc/service-example": {},
"/service-example": {}
},
Edit the content of the configuration file env.txt, and place it on the project path:
AWS_ACCESS_KEY_ID=<key_here>
AWS_SECRET_ACCESS_KEY=<secret_here>
AWS_DEFAULT_REGION=us-east-1
BACKUP_NAME=service-backup
PATHS_TO_BACKUP=/etc/service-example /service-example
S3_BUCKET_NAME=docker-backups.example.com
RESTORE=false
Run the dockup container
$ docker run --rm \
--env-file env.txt \
--volumes-from <service-name> \
--name dockup tutum/dockup:latest
Afterwards verify your s3 bucket contains the relevant data
docker container run --rm --volumes-from your_db_container -v $(pwd):/backup ubuntu tar cvf /backup/backup.tar /your_named_volume
run creates the new container
--rm option removes the container just after the execution of the tar cvf /backup/backup.tar /dbdata command
--volumes-from creates a named volume (your_named_volume) taken from the one you've created in your_db_container
-v $(pwd):/backup creates a bind mount between your current host directory ($(pwd)) and a /backup directory in your new container
tar cvf /backup/backup.tar /your_named_volume creates the archive
source: backup a volume
If you have a case as simple as mine was you can do the following:
Create a Dockerfile that extends the base image of your container
I assume that your volumes are mapped to your filesystem, so you can just add those files/folders to your image using ADD folder destination
Done!
For example, assuming you have the data from the volumes on your home directory, for example at /home/mydata you can run the following:
DOCKERFILE=/home/dockerfile.bk-myimage
docker build --rm --no-cache -t $IMAGENAME:$TAG -f $DOCKERFILE /home/pirate
Where your DOCKERFILE points to a file like this:
FROM user/myimage
MAINTAINER Danielo Rodríguez Rivero <example#gmail.com>
WORKDIR /opt/data
ADD mydata .
The rest of the stuff is inherited from the base image. You can now push that image to docker cloud and your users will have the data available directly on their containers
If you like entering arcane operators from the command line, you’ll love these manual container backup techniques. Keep in mind, there’s a faster and more efficient way to backup containers that’s just as effective. I've written instructions here: https://www.morpheusdata.com/blog/2017-03-02-how-to-create-a-docker-backup-with-morpheus
Step 1: Add a Docker Host to Any Cloud
As explained in a tutorial on the Morpheus support site, you can add a Docker host to the cloud of your choice in a matter of seconds. Start by choosing Infrastructure on the main Morpheus navigation bar. Select Hosts at the top of the Infrastructure window, and click the “+Container Hosts” button at the top right.
To back up a Docker host to a cloud via Morpheus, navigate to the Infrastructure screen and open the “+Container Hosts” menu.
Choose a container host type on the menu, select a group, and then enter data in the five fields: Name, Description, Visibility, Select a Cloud and Enter Tags (optional). Click Next, and then configure the host options by choosing a service plan. Note that the Volume, Memory, and CPU count fields will be visible only if the plan you select has custom options enabled.
Here is where you add and size volumes, set memory size and CPU count, and choose a network. You can also configure the OS username and password, the domain name, and the hostname, which by default is the container name you entered previously. Click Next, and then add any Automation Workflows (optional).Finally, review your settings and click Complete to save them.
Step 2: Add Docker Registry Integration to Public or Private Clouds
Adam Hicks describes in another Morpheus tutorial how simple it is to integrate with a private Docker Registry. (No added configuration is required to use Morpheus to provision images with Docker’s public hub using the public Docker API.)
Select Integrations under the Admin tab of the main navigation bar, and then choose the “+New Integration” button on the right side of the screen. In the Integration window that appears, select Docker Repository in the Type drop-down menu, enter a name and add the private registry API endpoint. Supply a username and password for the registry you’re using, and click the Save Changes button.
Integrate a Docker Registry with a private cloud via the Morpheus “New Integration” dialog box.
To provision the integration you just created, choose Docker under Type in the Create Instance dialog, select the registry in the Docker Registry drop-down menu under the Configure tab, and then continue provisioning as you would any Docker container.
Step 3: Manage Backups
Once you’ve added the Docker host and integrated the registry, a backup will be configured and performed automatically for each instance you provision. Morpheus support provides instructions for viewing backups, creating an instance backup, and creating a server backup.
I would suggest using restic. It's an easy to use backup application that can back up to various targets such as local file systems, S3 compatible storage services or a restic REST target server to mention some of the options. Using resticker, you will have an already prepared container that can be scheduled with cron syntax: https://github.com/djmaze/resticker
For the ones that want to learn more about restic and it's usage, I did write a blog post series on that topic including examples on its usage:
https://remo-hoeppli.medium.com/restic-backup-i-simple-and-beautiful-backups-bdbbc178669d
I have been using this batch script to back up all my volumes. The script takes the container name as the single argument, and automatically finds all its mounted volumes.
Then it creates one tar archive for each volume.
#! /bin/bash
container=$1
dirname="backup-$container-$(date +"%FT%H%M%z")"
mkdir $dirname
cd $dirname
volume_paths=( $(docker inspect $container | jq '.[] | .Mounts[].Name, .Mounts[].Source') )
volume_count=$(( ${#volume_paths[#]} / 2 ))
for i in $(seq $volume_count); do
volume_name=${volume_paths[i-1]}
volume_name=$(echo $volume_name | tr -d '"')
volume_path=${volume_paths[(i-1)+volume_count]}
volume_path=$(echo $volume_path | tr -d '"')
echo "$volume_name : $volume_path"
# create an archive with volume name
tar -zcvf "$volume_name.tar" $volume_path
done
The code is available at Github.
This is a volume-folder-backup way.
If you have docker registry infra, This method is very helpful.
This uses docker registry for moving the zip file easily.
#volume folder backup script. !/bin/bash
#common bash variables. set these variable before running scripts
REPO=harbor.otcysk.org:20443/levee
VFOLDER=/data/mariadb
TAG=mariadb1
#zip local folder for volume files
tar cvfz volume-backup.tar.gz $VFOLDER
#copy the zip file to volume-backup container.
#zip file must be in current folder.
docker run -d -v $(pwd):/temp --name volume-backup ubuntu \
bash -c "cd / && cp /temp/volume-backup.tar.gz ."
#commit for pushing into REPO
docker commit volume-backup $REPO/volume-backup:$TAG
#check gz files in this container
#docker run --rm -it --entrypoint bash --name check-volume-backup \
$REPO/volume-backup:$TAG
#push into REPO
docker push $REPO/volume-backup:$TAG
In another server
#pull the image in another server
docker pull $REPO/volume-backup:$TAG
#restore files in another server filesystem
docker run --rm -v $VFOLDER:$VFOLDER --name volume-backup $REPO/volume-backup:$TAG \
bash -c "cd / && tar xvfz volume-backup.tar.gz"
Run your image which uses this volume folder.
You can make a image which has both one run-image and one volume zip file easily.
But I do not recommened for various reasons(image size, entry command, ..).