Docker How To Access File System
It can be important to be able to access the file system of a Docker container. You might want to do this for different reasons including testing, debugging, or just data sharing in production.
Method1 - Get a Shell
If you just want to be able to quickly access the file system on a Docker container you can use the following to get a shell. This will allow you to explore the FS and poke around all you want.
docker exec -ti my-container1 /bin/bash
If you don’t want to connect directly to your container you could also create a snapshot, run it with a shell, and connect to that like this:
docker commit 12345678904b5 snapshot1 docker run -t -i snapshot1 /bin/bash
Method 2 - Quick Copy
You can copy files directly off of a container to your local host like this:
sudo docker cp my-container1:/data1/output.csv /home/user1/mydir
Method 3 - Use a Volume
You can run a container with a local directory bind mounted inside:
docker run -d --name my-container1 -v /src/data:/data ubuntu
You can also do this in read only mode:
docker run -d --name my-container1 -v /src/data:/data:ro ubuntu
Alternative Methods to access a Container’s File System
You could also runan ssh daemon and use SCP to transfer files between the container and other hosts.
Launch sshd on the container like this ( exposed on port 12345 ):
docker run -d -p 12345:22 my-container1 /usr/sbin/sshd -D
Use scp to copy data off like this:
scp -P 12345 email@example.com:/data/output.txt /home/user1/output.txt
You could also just ssh right in like this:
ssh -p 12345 firstname.lastname@example.org
Another option would be to set up a samba share on your container. While this is an option you might just be better off using a volume.
Check out our guide here: Samba Setup.