Data not copying to volume upon initialization

[PrymalInstynct]

/kind Bug

Description

Migrating Container environment from Docker to Podman

Creating Container image with application installed (rpm), this application expects data to be persistent is various directories within its install path. My solution to deal with this is to create a volume and attach that volume to the application root path within the container. In Docker the contents of the containers application directory structure would be copied into the volume when it first startes. This is not happening via podman.

Steps to reproduce the issue:

1. Using the same container image with both Docker & Podman

2. podman volume create sc_data

3. podman run -d -v sc_data:/opt/sc -p 8443:443 sc_image

Describe the results you received:

podman logs <container>
/usr/bin/start-sc.sh: line 11: /opt/sc/support/bin/httpd: No such file or directory

ls -l /var/lib/containers/storage/volumes/sc_data/_data/
total 0

Describe the results you expected:

I would expect that the contents of /opt/sc would be copied to the volume sc_data and the container would start. This happens when running the image with docker.

Additional information you deem important (e.g. issue happens only occasionally):

Output of podman version:

Version:            1.4.4
RemoteAPI Version:  1
Go Version:         go1.10.8
OS/Arch:            linux/amd64

Output of podman info --debug:

debug:
  compiler: gc
  git commit: ""
  go version: go1.10.8
  podman version: 1.4.4
host:
  BuildahVersion: 1.9.0
  Conmon:
    package: podman-1.4.4-3.el7.x86_64
    path: /usr/libexec/podman/conmon
    version: 'conmon version 0.3.0, commit: unknown'
  Distribution:
    distribution: '"rhel"'
    version: "7.7"
  MemFree: 4896395264
  MemTotal: 8369545216
  OCIRuntime:
    package: runc-1.0.0-65.rc8.el7.x86_64
    path: /usr/bin/runc
    version: 'runc version spec: 1.0.1-dev'
  SwapFree: 8342466560
  SwapTotal: 8455712768
  arch: amd64
  cpus: 4
  hostname: podman01
  kernel: 3.10.0-1062.el7.x86_64
  os: linux
  rootless: false
  uptime: 455h 16m 31.45s (Approximately 18.96 days)
registries:
  blocked: null
  insecure: null
  search:
  - registry.access.redhat.com
  - docker.io
  - registry.fedoraproject.org
  - quay.io
  - registry.centos.org
store:
  ConfigFile: /etc/containers/storage.conf
  ContainerStore:
    number: 1
  GraphDriverName: overlay
  GraphOptions: null
  GraphRoot: /var/lib/containers/storage
  GraphStatus:
    Backing Filesystem: xfs
    Native Overlay Diff: "true"
    Supports d_type: "true"
    Using metacopy: "false"
  ImageStore:
    number: 3
  RunRoot: /var/run/containers/storage
  VolumePath: /var/lib/containers/storage/volumes

Package info (e.g. output of rpm -q podman or apt list podman):

podman-1.4.4-3.el7.x86_64

Additional environment details (AWS, VirtualBox, physical, etc.):

Host is virtualized with VMWare

[mheon]

Hmm. We migrate data into the volume when it's creating with the container (e.g. podman run --volume doesnotexist:/mountpoint ... would copy the contents of /mountpoint into the container into the doesnotexist volume as part of creating it). Let me double-check that Docker also copies for first instance of mounting after create, as well

[mheon]

Hm. It looks like Docker does copy contents to the volume on first mount. I'll look into adding this.

[PrymalInstynct]

Thanks for investigating, this function is critical to what I am trying to accomplish.

[rhatdan]

@mheon Should we assign this to @QiWang19?

[mheon]

Eh, I'm in there already for adding volume driver support, and this one shouldn't be more than a half hour of work now that I am.

[rhatdan]

Ok.

[pycloux]

Don't know if this is "on purpose" but the behavior is still different from Docker default one.
If you mount an "empty" volume into a docker container to a new path (say "/opt/test") and then mount the same volume to another container to a "non-empty" path, then the content of the "non-empty" path will be copied on to the volume.
With Podman (I just tested it with the version 3.3.1), the volume will remain "empty" as soon as it was mounted to one container. Docker is more permissive and will allow the data to be copied if the volume is empty.

[rhatdan]

Please open a new issue.