Docker: How to live sync host folder with container folder?

Question

I am working on a website powered by Node. So I have made a simple Dockerfile that adds my site's files to the container's FS, installs Node and runs the app when I run the container, exposing the private port 80.

But if I want to change a file for that app, I have rebuild the container image and re-run it. That takes some seconds.

Is there an easy way to have some sort of "live sync", NFS like, to have my host system's app files be in sync with the ones from the running container?

This way I only have to relaunch it to have changes apply, or even better, if I use something like supervisor, it will be done automatically.

Possible duplicate of Mounting multiple volumes on a docker container? — Sergiu
– Sergiu, Commented Sep 20, 2017 at 18:34

Matt · Accepted Answer · 2016-08-11 07:34:28Z

60

You can use volumes in order to do this. You have two options:

Docker managed volumes:

docker run -v /src/path nodejsapp docker run -i -t -volumes-from <container id> bash

The file you edit in the second container will update the first one.

Host directory volume:

docker run -v `pwd`/host/src/path:/container/src/path nodejsapp

The changes you make on the host will update the container.

edited Aug 11, 2016 at 7:34

Matt

75.7k11 gold badges172 silver badges167 bronze badges

answered Sep 18, 2013 at 18:56

creack

123k12 gold badges101 silver badges73 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

Simon Forsberg Over a year ago

Note that the path, where you have written `pwd`/host/src/path needs to be absolute path (for example just /host/src/path). If you use a relative path, it will not synchronize correctly between the host and the container.

Chung Lun Yuen Over a year ago

Doesn't pwd always return absolute path?

OZZIE Over a year ago

should I write "/host/" and "/container/" or this is the filepath on those systems? the or the container name? what is the host called then? I just want to sync the files from my mac to docker, should I do 1 or 2 then or both?

OZZIE Over a year ago

I get docker: invalid reference format: repository name must be lowercase. using -ditv if I don't use the flags -dit then the container terminates after the command

mirageglobe · Accepted Answer · 2018-11-21 01:58:54Z

If you are under OSX, those kind of volume shares can become very slow, especially with node-based apps ( a lot of files ). For this issue, http://docker-sync.io can help, by providing a volume-share like synchronisation, without using volume shares, this usually speeds up your container read/write speed of the code-directory from 50-80 times, depending on what docker-machine you use.

For performance see https://github.com/EugenMayer/docker-sync/wiki/4.-Performance and for easy examples how to use it, see the boilerplates https://github.com/EugenMayer/docker-sync-boilerplate for your case the unison example https://github.com/EugenMayer/docker-sync-boilerplate/tree/master/unison is the one you would need for NFS like sync

It does not work for windows, right? Do you know an alternative?
It does not work with Docker Toolbox on Windows. However, it does work with Docker for Windows, which requires Windows 10 (but not Home Edition).
Works with osx/windows/linux and freebsd(0.5.0) - but yes some strategies like native_osx are OSX only, and also some docker-engines
This may be unnecessary from Docker App 4.7 through VirtioFs experimental feature: virtio-fs.gitlab.io

Rexcirus · Accepted Answer · 2019-12-16 10:11:49Z

docker run -dit -v ~/my/local/path:/container/path/ myimageId

For /container/path/ you could use for instance /usr/src/app. The flags:

-d = detached mode,

-it = interactive,

-v + paths = specifies the volume.

(If you just care about the volume, you can drop the -dit flag.)

Docker run reference

-d = detached mode, -it = interactive, -v specifies the volume. If you just care about the volume, you can drop the -dit flag. docs.docker.com/engine/reference/run

Venryx · Accepted Answer · 2021-08-09 01:11:22Z

I use Scaffold's File Sync functionality for this. It gets the job done, and without needing overly complex configuration.

Setting up Scaffold in my project was as simple as installing Skaffold (through chocolatey, since I'm on Windows), running skaffold init --generate-manifests in my project folder, and answering a couple questions it asked.

Collectives™ on Stack Overflow

Docker: How to live sync host folder with container folder?

4 Answers 4

4 Comments

4 Comments

1 Comment

Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

4 Comments

4 Comments

1 Comment

Comments

Linked

Related