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I have a docker with version 17.06.0-ce . When I trying to install NGINX using docker with command:

docker run -p 80:80 -p 8080:8080 --name nginx -v $PWD/www:/www -v $PWD/conf/nginx.conf:/etc/nginx/nginx.conf -v $PWD/logs:/wwwlogs -d nginx:latest

It shows that

docker: Error response from daemon: oci runtime error: container_linux.go:262: starting container process caused "process_linux.go:339: container init caused \"rootfs_linux.go:57: mounting \\"/appdata/nginx/conf/nginx.conf\\" to rootfs \\"/var/lib/docker/aufs/mnt/dcea22444e9ffda114593b18fc8b574adfada06947385aedc2ac09f199188fa0\\" \\"/var/lib/docker/aufs/mnt/dcea22444e9ffda114593b18fc8b574adfada06947385aedc2ac09f199188fa0/etc/nginx/nginx.conf\\" caused \\"not a directory\\"\"" : Are you trying to mount a directory onto a file (or vice-versa)? Check if the specified host path exists and is the expected type.

If do not mount the nginx.conf file, everything is okay. So, how can I mount the configuration file?

In my case I had accidentally mapped a directory from the host to a file in the container. Restarting the container didn't work anymore. I had to remove the container (docker rm …), then recreate it. – slhck Mar 12, 2019 at 12:17

This should no longer happen (since v2.2.0.0), see here

If you are using Docker for Windows, this error can happen if you have recently changed your password.

How to fix:

  • First make sure to delete the broken container's volume
    docker rm -v <container_name>
    Update: The steps below may work without needing to delete volumes first.
  • Open Docker Settings
  • Go to the "Shared Drives" tab
  • Click on the "Reset Credentials..." link on the bottom of the window
  • Re-Share the drives you want to use with Docker
  • You should be prompted to enter your username/password
  • Click "Apply"
  • Go to the "Reset" tab
  • Click "Restart Docker"
  • Re-create your containers/volumes
  • Credit goes to BaranOrnarli on GitHub for the solution.

    I was able to fix the problem by starting on step 2 and also omitting the last one. I did not have to destroy the containers/volumes to mount again. – Christian Engel Aug 10, 2018 at 9:57 I agree with @MateoHermosilla, it dosen't need to dete the container, only "Reset Credentials" – sintetico82 Dec 10, 2018 at 11:17 I'm getting the same error when trying to run proxy-deploy.sh while installing sandbox-proxy (hadoop). Following this soln. did not fix it. – Vaibhav Dec 23, 2018 at 19:41 This was the issue for me. Password reset is every few months, so I keep forgetting to reset Shared Drive credentials in Docker. – Anders Marzi Tornblad Feb 26, 2019 at 11:01

    TL;DR: Remove the volumes associated with the container.

    Find the container name using docker ps -a then remove that container using:

    docker rm -v <container_name>
    

    Problem:

    The error you are facing might occur if you previously tried running the docker run command while the file was not present at the location where it should have been in the host directory.

    In this case docker daemon would have created a directory inside the container in its place, which later fails to map to the proper file when the correct files are put in the host directory and the docker command is run again.

    Solution:

    Remove the volumes that are associated with the container. If you are not concerned about other container volumes, you can also use:

    # WARNING, THIS WILL REMOVE ALL VOLUMES
    docker volume rm $(docker volume ls -q)
                    The command in the original question only listed host volumes as being used. The docker volume command/interface is only for anonymous and named volumes, which are not part of the original question.
    – programmerq
                    Aug 31, 2017 at 16:54
                    @programmerq Look at the error, it says that mount was failing when it tried to mount at /var/lib/docker/aufs/mnt/dcea22444e9ffda114593b18fc8b574adfada06947385aedc2ac09f199188fa0\\\" My deduction: It already has a folder due to a previous run, so if you try to map a file to that folder, it would fail.
    – Ayushya
                    Aug 31, 2017 at 20:28
                    Here two things might have gone wrong, either the host has wrong things, or already created volume has incorrect thing. Assuming host to be correct, I thought it would be better to clear issues with existing volume.
    – Ayushya
                    Aug 31, 2017 at 20:33
                    This is actually a valid answer for when the container has already been associated with a volume and the type of that volume is being changed in the next run. So removing volume might help!
    – Yan Foto
                    Sep 13, 2017 at 9:50
                    This was helpful. The problem in my case was indeed that I had old containers still defined. Using docker rm to zap them and then doing a docker-compose up worked properly.
    – Max Tardiveau
                    Nov 8, 2018 at 0:04
    

    Because docker will recognize $PWD/conf/nginx.conf as a folder and not as a file. Check whether the $PWD/conf/ directory contains nginx.conf as a directory.

    Test with

    > cat $PWD/conf/nginx.conf 
    cat: nginx.conf/: Is a directory
    

    Otherwise, open a Docker issue.
    It's working fine for me with same configuration.

    As an intermediate-level Linux user I'm curious, what's the reason for Linux recognizing that as a folder and not a file? – J. Scott Elblein Sep 3, 2020 at 18:04 Because it is actually a folder. If the file doesn't exist, docker create a folder because of the volume argument -v – callmemath Sep 4, 2020 at 3:07 ok, so Linux only recognizes it as a folder if docker had to create it due to the path not previously existing; but if the nginx.conf did already previously exist at that path Linux would recognize it as a file, right? – J. Scott Elblein Sep 4, 2020 at 3:40

    The explanation given by @Ayushya was the reason I hit this somewhat confusing error message and the necessary housekeeping can be done easily like this:

    $ docker container prune
    $ docker volume prune
    

    Answer for people using Docker Toolbox

    There have been at least 3 answers here touching on the problem, but not explaining it properly and not giving a full solution. This is just a folder mounting problem.

    Description of the problem:

    Docker Toolbox bypasses the Hyper-V requirement of Docker by creating a virtual machine (in VirtualBox, which comes bundled). Docker is installed and ran inside the VM. In order for Docker to function properly, it needs to have access to the from the host machine. Which here it doesn't.

    After I installed Docker Toolbox it created the VirtualBox VM and only mounted C:\Users to the machine, as \c\Users\. My project was in C:\projects so nowhere on the mounted volume. When I was sending the path to the VM, it would not exist, as C:\projects isn't mounted. Hence, the error above.

    Let's say I had my project containing my ngnix config in C:/projects/project_name/

    Fixing it:

  • Go to VirtualBox, right click on Default (the VM from Docker) > Settings > Shared Folders

  • Clicking the small icon with the plus on the right side, Add a new share. I used the following settings:

  • Restart everything and it should now work properly. I manually stopped the virtual machine in VirtualBox and restarted the Docker Toolbox CLI.
  • In my docker file, I now reference the nginx.conf like this:

    volumes:
        - /projects/project_name/docker_config/nginx/nginx.conf:/etc/nginx/conf.d/default.conf
    

    Where nginx.conf actually resides in C:\projects\project_name\docker_config\nginx\nginx.conf

    I had the same problem. I was using Docker Desktop with WSL in Windows 10 17.09.

    Cause of the problem:

    The problem is that Docker for Windows expects you to supply your volume paths in a format that matches this:

    /c/Users/username/app

    BUT, WSL instead uses the format:

    /mnt/c/Users/username/app

    This is confusing because when checking the file in the console I saw it, and for me everything was correct. I wasn't aware of the Docker for Windows expectations about the volume paths.

    Solution to the problem:

    I binded the custom mount points to fix Docker for Windows and WSL differences:

    sudo mount --bind /mnt/c /c

    Like suggested in this amazing guide: Setting Up Docker for Windows and WSL to Work Flawlessly and everything is working perfectly now.

    Before I started using WSL I was using Git Bash and I had this problem as well.

    I found this after I solved it. My solution was to move the current folder with my host mount files from my home dir to /e/ (which is another drive, mounted as you explained in your answer) to get it to work. I appreciate your comment that you explain what the problem was, I just realized my solution worked but not why. – Arizon Aug 17, 2022 at 10:27 Thank you this solved my issue. I also turned off use Docker Compose v2 in the Experimental Features section. – Jafferwaffer Jun 23, 2021 at 15:45

    Maybe someone finds this useful. My compose file had following volume mounted

    ./file:/dir/file
    

    As ./file did not exist, it was mounted into ABC (by default as folder).

    In my case I had a container resulted from

    docker commit ABC cool_image
    

    When I later created ./file and ran docker-compose up , I had the error:

    [...] Are you trying to mount a directory onto a file (or vice-versa)? Check if the specified host path exists and is the expected type.

    The container brought up from cool_image remembered that /dir/file was a directory and it conflicted with lately created and mounted ./file .

    The solution was:

    touch ./file
    docker run abc_image --name ABC -v ./file:/dir/file
    # ... desired changes to ABC
    docker commit ABC cool_image
    

    I am using Docker ToolBox for Windows. By default C Drive is mounted automatically, so in order to mount the files, make sure your files and folders are inside C DRIVE.

    Example: C:\Users\%USERNAME%\Desktop

    my mounted folder is C:\x-suite\ ; I shared my C drive ,but still have not solved my problem – 袁文涛 Feb 19, 2019 at 3:29 minikube+virtualBox+docker ToolBox , localkube was deprecated, what driver should I use? – 袁文涛 Feb 20, 2019 at 11:39

    unknown: Are you trying to mount a directory onto a file (or vice-versa)? Check if the specified host path exists and is the expected type

    I had a similar error on niginx in Mac environment. Docker didn't recognize the default.conf file correctly. Once changing the relative path to the absolute path, the error was fixed.

          - ./nginx/default.conf:/etc/nginx/conf.d/default.conf
    

    I'll share my case here as this may save a lot of time for someone else in the future.

    I had a perfectly working docker-compose on my macos, until I start using docker-in-docker in Gitlab CI. I was only given permissions to work as Master in a repository, and the Gitlab CI is self-hosted and setup by someone else and no other info was shared, about how it's setup, etc.

    The following caused the issue:

    volumes:
      - ./.docker/nginx/wordpress/wordpress.conf:/etc/nginx/conf.d/default.conf
    

    Only when I noticed that this might be running under windows (hours scratching the head), I tried renaming the wodpress.conf to default.conf and just set the dir pathnames:

    volumes:
      - ./.docker/nginx/wordpress:/etc/nginx/conf.d
    

    This solved the problem!

    Not a bad decision) I had a problem that I could not copy the file to the directory named conf.d And I solved it by copying the entire contents of one directory to another – andrew kot Jul 6, 2022 at 13:56

    I had the same issue, docker-compose was creating a directory instead of file, then crashing mid-way.

    What I did:

  • Run the container without any mapping.

  • Copy the .conf file to the host location:

    docker cp containername:/etc/nginx/nginx.conf ./nginx.conf

  • Remove the container (docker-compose down).

  • Put the mapping back.

  • Re-mount the container.

    Docker Compose will find the .conf file and map it, instead of trying to create a directory.

    In Windows 10, I just get this error without changing anything in my docker-compose.yml file or Docker configuration in general.

    In my case, I was using a VPN with a firewall policy that blocks port 445.

    After disconnecting from the VPN the problem disappears.

    So I recommend checking your firewall and not using a proxy or VPN when running Docker Desktop.

    Check Docker for windows - Firewall rules for shared drives for more details.

    I hope this will help someone else.

    Could you please use the absolute/complete path instead of $PWD/conf/nginx.conf? Then it will work.

    EX:docker run --name nginx-container5 --rm  -v /home/sree/html/nginx.conf:/etc/nginx/nginx.conf -d -p 90:80 nginx
    b9ead15988a93bf8593c013b6c27294d38a2a40f4ac75b1c1ee362de4723765b
    root@sree-VirtualBox:/home/sree/html# docker ps
    CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                NAMES
    b9ead15988a9        nginx               "nginx -g 'daemon of…"   7 seconds ago       Up 6 seconds        0.0.0.0:90->80/tcp   nginx-container5
    e2b195a691a4        nginx               "/bin/bash"              16 minutes ago      Up 16 minutes       0.0.0.0:80->80/tcp   test-nginx
                    if you escape it with double-quotes : docker run -d --rm -v "$PWD/nginx.conf:/etc/nginx/nginx.conf" nginx it should make no difference as the shell will translate it before passing it to docker run and actually, it doesn't make a difference, at least for me
    – Manumie
                    Mar 27, 2020 at 13:44
    

    I experienced the same issue using Docker over WSL1 on Windows 10 with this command line:

    echo $PWD
    /mnt/d/nginx
    docker run --name nginx -d \
      -v $PWD/conf/nginx.conf:/etc/nginx/nginx.conf \
    nginx
    

    I resolved it by changing the path for the file on the host system to a UNIX style absolute path:

    docker run --name nginx -d \
      -v /d/nginx/conf/nginx.conf:/etc/nginx/nginx.conf \
    nginx
    

    or using an Windows style absolute path with / instead of \ as path separators:

    docker run --name nginx -d \
      -v D:/nginx/conf/nginx.conf:/etc/nginx/nginx.conf \
    nginx
    

    To strip the /mnt that seems to cause problems from the path I use bash variable extension:

    -v ${PWD/mnt\/}/conf/nginx.conf:/etc/nginx/nginx.conf
                    Did you notice any performance differences when using the Windows style path vs. the Unix style path?
    – J. Scott Elblein
                    Sep 3, 2020 at 18:09
                    I can't tell. I'm just using Docker for Windows for testing/development and never monitored performance.
    – bwibo
                    Sep 4, 2020 at 15:18
    

    Updating Virtual Box to 6.0.10 fixed this issue for Docker Toolbox

    https://github.com/docker/toolbox/issues/844

    I was experiencing this kind of error:

    mlepisto@DESKTOP-VKJ76GO MINGW64 ~/G/Projects $ touch resolv.conf mlepisto@DESKTOP-VKJ76GO MINGW64 ~/G/Projects $ docker run --rm -it -v $PWD/resolv.conf:/etc/resolv.conf ubuntu /bin/bash C:\Program Files\Docker Toolbox\docker.exe: Error response from daemon: OCI runtime create failed: container_linux.go:345: starting container process caused "process_linux.go:430: container init caused \"rootfs_linux.go:58: mounting \\\"/c/Users/mlepisto/G/Projects/resolv.conf\\\" to rootfs \\\"/mnt/sda1/var/lib/docker/overlay2/61eabcfe9ed7e4a87f40bcf93c2a7d320a5f96bf241b2cf694a064b46c11db3f/merged\\\" at \\\"/mnt/sda1/var/lib/docker/overlay2/61eabcfe9ed7e4a87f40bcf93c2a7d320a5f96bf241b2cf694a064b46c11db3f/merged/etc/resolv.conf\\\" caused \\\"not a directory\\\"\"": unknown: Are you trying to mount a directory onto a file (or vice-versa)? Check if the specified host path exists and is the expected type. # mounting to some other file name inside the container did work just fine mlepisto@DESKTOP-VKJ76GO MINGW64 ~/G/Projects/ $ docker run --rm -it -v $PWD/resolv.conf:/etc/resolv2.conf ubuntu /bin/bash root@a5020b4d6cc2:/# exit

    After updating VitualBox all commands did work just fine 🎉

    Had the same head scratch because I did not have the file locally so it created it as a folder.

    mimas@Anttis-MBP:~/random/dockerize/tube$ ls
    Dockerfile
    mimas@Anttis-MBP:~/random/dockerize/tube$ docker run --rm -v $(pwd)/logs.txt:/usr/app/logs.txt devopsdockeruh/first_volume_exercise
    docker: Error response from daemon: OCI runtime create failed: container_linux.go:345: starting container process caused "process_linux.go:430: container init caused \"rootfs_linux.go:58: mounting \\\"/Users/mimas/random/dockerize/tube/logs.txt\\\" to rootfs \\\"/var/lib/docker/overlay2/75891ea3688c58afb8f0fddcc977c78d0ac72334e4c88c80d7cdaa50624e688e/merged\\\" at \\\"/var/lib/docker/overlay2/75891ea3688c58afb8f0fddcc977c78d0ac72334e4c88c80d7cdaa50624e688e/merged/usr/app/logs.txt\\\" caused \\\"not a directory\\\"\"": unknown: Are you trying to mount a directory onto a file (or vice-versa)? Check if the specified host path exists and is the expected type.
    mimas@Anttis-MBP:~/random/dockerize/tube$ ls
    Dockerfile  logs.txt/
    

    I had this problem under Windows 7 because my dockerfile was on different drive.

    Here's what I did to fix the problem:

  • Open VirtualBox Manager
  • Select the "default" container and edit the settings.
  • Select Shared Folders and click the icon to add a new shared folder
  • Folder Path: x:\
  • Folder Name: /x
  • Check Auto-mount and Make Permanent
  • Restart the virtual machine
  • At this point, docker-compose up should work.

    ... caused \\\"not a directory\\\"\"": unknown: Are you trying to mount a directory onto a file (or vice-versa)? Check if the specified host path exists and is the expected type

    I was using absolute paths like this //C/workspace/nginx/nginx.conf and everything worked like a charm.
    The update broke my docker-compose, and I had to change the paths to /C/workspace/nginx/nginx.conf with a single / for the root.

    Adding the root path as a file sharing resource will now permit Docker to access the resource to mount it to the container. Note that you may need to erase the contents on your Docker container to attempt to re-mount the volume.

    For example, if your application is located at /mysites/myapp, you will want to add /mysites as the file sharing resource location.

    In my case it was a problem with Docker for Windows and use partition encrypted by Bitlocker. If you have project files on encrypted files after restart and unlock drive Dokcer doesn't see project files properly.

    All you need to do is just need to restart Docker

    CleanWebpackPlugin can be the problem. In my case, in my Docker file I copy a file like this:

    COPY --chown=node:node dist/app.js /usr/app/app.js
    

    and then during development I mount that file via docker-compose:

     volumes:
          - ./dist/app.js:/usr/app/app.js
    

    I would intermittently get the Are you trying to mount a directory onto a file (or vice-versa)? Check if the specified host path exists and is the expected type. error or some version of it.

    The problem was that the CleanWebpackPlugin was deleting the file and before webpack re-built. If Docker was trying to mount the file while it was deleted Docker would fail. It was intermittent.

    Either remove CleanWebpackPlugin completely or configure its options to play nicer.

    l have solved the mount problem. I am using a Win 7 environment, and the same problem happened to me.

    Are you trying to mount a directory onto a file?

    The container has a default sync directory at C:\Users\, so I moved my project to C:\Users\, then recreated the project. Now it works.

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