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So I have a machine running several Docker containers (I use Portainer to manage it if useful). Every container has various volumes attached and run on various networks.
Is there a simple and fast way to port the entire configuration to another host?
i can’t find a single all-in-one solution for this task
You can try to stop the docker daemon, create a tar archive from the docker root-data directory on your old host and untar the archive on the new host. Of course everything done as root user.
Though, it depends if your current system and your new system will use the same storage driver, otherwise the new storage driver will prevent docker from using the restored data.
Personally, I would backup the content of volumes instead and restore the backups on the new host, then clone the git repos that store my compose files, then re-create the conatiners from the compose files.
I agree with @meyay and I would also add if you move an existing docker data root to another host, there is also a risk to have wrong network bridges / Docker IP address if that machine is in a different network or if that machine already has networks creatd by something else.
Thanks a lot @meyay and @rimelek for the answers.
I think moving the volumes attached to every container should do the job. Is there a guide to do that, considering every container I use has at least two volumes attached to it?
Thanks
So I’ve tried according to the documentation but it seems not working…
This specific instance is a backup of a volume containing grafana data at /var/lib/grafana
The backup has been done with docker run --rm --volumes-from Grafana -v $(pwd):/backup busybox tar cvfz /backup/grafana.tar /var/lib/grafana
Where Grafana is the name of the container where the volume is attached
On my new host, after having transferred the grafana.tar file I’ve run
docker run --rm --volumes-from grafana-new -v $(pwd):/backup busybox sh -c "cd /var/lib/grafana && tar xvf /backup/grafana.tar --strip 1"
Where grafana-new is the new container that has attached a volume with the same path in the container /var/lib/grafana
The issue is that it doesn’t seem to restore the data even if I see it on the terminal
nicola@nicola-virtualbox:~/Documenti/volume-backup$ docker run --rm --volumes-from grafana-new -v $(pwd):/backup busybox sh -c "cd /var/lib/grafana && tar xvf /backup/grafana.tar --strip 1"
var/lib/grafana/
var/lib/grafana/png/
var/lib/grafana/csv/
var/lib/grafana/plugins/
var/lib/grafana/alerting/
var/lib/grafana/alerting/1/
var/lib/grafana/alerting/1/__default__.tmpl
var/lib/grafana/grafana.db
I’m saying that because when I’m trying to log in with the password used on the host from where I’ve backed the data, it says the wrong password
Instead of --volumes-from grafana-new make sure to mount the volume instead. I am not sure if bind volume (-v /host/path:/container/path) are included when using --volumes-from.
Furthermore, make sure the volume is not used when you perform your backup to be sure to create consistent backups
I used this approach to back up volumes in the past:
# check `docker volume ls´ for volume names
source_volume=name_of_your_source_volume
backup_date=$(date +"%Y%m%d")
docker run --tty --rm --interactive --volume ${source_volume}:/source --volume ${PWD}/archive:/backup alpine tar czvf /backup/${source_volume}_${backup_date}.tar.gz -C /source .
And restored them like this:
target_volume=name_of_your_target_volume
restore_archive=${volume}_${backup_date}.tar.gz # of course the real name without placeholders
docker run --tty --rm --interactive --volume ${target_volume}:/target --volume ${PWD}/archive:/backup alpine tar xzvf /backup/${restore_archive} -C /target
Works like a charme.
When I’m trying to restore it I’m having
tar: can't open '/backup/grafana-storage_20230825.tar.gz': No such file or directory
The code I’m using
target_volume=grafana-storage
restore_archive=grafana-storage_20230825.tar.gz
docker run --tty --rm --interactive --volume ${target_volume}:/target --volume ${PWD}/archive:/backup alpine tar xzvf /backup/${restore_archive} -C /target
I’ve correctly created the grafana-storage volume before launching the command and I’m launching the command inside after having cd inside the folder containing grafana-storage_20230825.tar.gz
It turned out I needed to have the folder /archive/ with inside the tar with the backup to make it work
I just happened to have the files in archive subfolder. You did right by moving the file into the expected path. Though you could have removed the archive folder from the -v binding as well.
Note: the path is supposed to be relative to the current folder. An absolute path would require a change in the -v binding as well.
Hello, can you please share as example how you edited the comands to create the tar.gz file, I am traying to follow using the below comand but always return an empty file:
source_volume=grafana-volume
backup_date=$(date +“%Y%m%d”)
sudo docker run --tty --rm --interactive --volume ${source_volume}:/source --volume ${PWD}/archive:/backup alpine tar czvf /backup/${source_volume}_${backup_date}.tar.gz -C /source
Please notice how the reference command I shared had a dot at the end of the line:
Thank you @meyay it was just the dot, the commands are really good, I spent many hours trying with the official instructions and other tutorials based on it without success, but these commands are great!
Hello! I have the same problem! I have managed to migrate my volume in the new host (thanks a lot @meyay for all the help), but I am not sure how I can connect it to the new container. Do you have any ideas on how to do that? Thank you in advance for your time!!
Can you extend on what “I am not sure how I can connect it to the new container” means exactly?
Please explain it in a way, so that someone who has no idea about
@meyay @nicocaldo Hello guys, i am working on migration of the images (from Linux) to a new host (on windows). I could migrate the image and create the volume (with the data) via docker run. The issue that I have right now, i am trying to attach the volume to the running container. The last step that i am trying is to mount the linux path (/var/lib/grafana). On Linux i did the following command (chmod 777 /var/lib/grafana) to change the rights of the folder. How can I find the path of grafana on windows. I could find the migrated volume on my network directory , but I can not change the rights of it.