Move docker container and volume to a new host

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Move docker container and volume to another host

Image and container

My understanding about image and container:
Container is a running image;
Image is a stopped container.

move a container

  • export current container (files) into a image 
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    docker export <CONTAINER ID> > /home/export.tar
  • Transfer to remote host (e.g. sftp)
  • Import image in remote host
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    cat /home/export.tar | docker import - some-name:latest

Note: ‘docker export’ exports all files but not command

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docker run -d -p 8787:8787 -e PASSWORD=yourpasswordhere rocker/rstudio:3.2.0

The command of running genunie Rstudio image does not specifiy a command

When running imported image

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sudo docker run -d -ti  --rm -p 8787:8787 --name RStudioServer --mount source=R_data,target=/home/rstudio/rdata   rstudio:new
docker: Error response from daemon: No command specified.

We need to go back to the original host to find the command:

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sudo docker ps
d79a11d5b7d0        rocker/rstudio:cancer_prediction   "/init"             15 minutes ago      Up 11 minutes       0.0.0.0:8787->8787/tcp   RStudioServer

We can see the command is ‘/init’

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sudo docker run -d -ti  --rm -p 8787:8787  --name RStudioServer --mount source=R_data,target=/home/rstudio/rdata   rstudio:fromTesla /init

Move a volume

There is no a magic command to move a volume.
My practise is compressing the whole directory and copying into the new container (mount the same entry point).