container/podman
container/podman
1
0
Fork 0
mirror of https://github.com/containers/podman synced 2024-10-20 01:03:51 +00:00
Code Issues Packages Projects Releases Wiki Activity
podman/contrib/helloimage
History
tomsweeneyredhat 40ba9f10e5 Make the hello image leaner 
[NO TESTS NEEDED]

Change from using a bash script to a c file
for running the image.  With thanks to discussions
with @afbjorklund, the Containerfile was rigged
up to make the final image be only KB's in size.

Also add USER 1000 to make the image test/run as
non-root, and update the README.md

Signed-off-by: tomsweeneyredhat <tsweeney@redhat.com>
2022-02-10 15:45:04 -05:00
..
Containerfile Make the hello image leaner 2022-02-10 15:45:04 -05:00
podman_hello_world.c Make the hello image leaner 2022-02-10 15:45:04 -05:00
README.md Make the hello image leaner 2022-02-10 15:45:04 -05:00

README.md

PODMAN logo

Podman Hello World image

Overview

This directory contains the Containerfile and bash script necessary to create the "hello" podman image housed on quay.io under the Podman account in a public repository. The image is public and can be pulled without credentials.

Using this image is helpful to:

  • Prove that basic Podman operations are working on the host.
  • Shows that the image was pulled from the quay.io container registry.
  • Container creation was successfuly accomplished. (podman ps -a)
  • The created container was able to stream output to your terminal.

Directory Contents

The contents of this directory contain:

  • ./Containerfile
  • ./podman_hello_world.c

Sample Usage

To simply run the image:

podman run quay.io/podman/hello

!... Hello Podman World ...!

         .--"--.
       / -     - \
      / (O)   (O) \
   ~~~| -=(,Y,)=- |
    .---. /`  \   |~~
 ~/  o  o \~~~~.----. ~~
  | =(X)= |~  / (O (O) \
   ~~~~~~~  ~| =(Y_)=-  |
  ~~~~    ~~~|   U      |~~

Project:   https://github.com/containers/podman
Website:   https://podman.io
Documents: https://docs.podman.io
Twitter:   @Podman_io

To build the image yourself, copy the files from this directory into a local directory and issue these commands:

podman build -t myhello .
podman run myhello

Potential Issues:

The image runs as a rootless user with the UID set to 1000. If the /etc/subuid and /etch/subgid values are not set appropriately to run as a rootless user on the host, an error like this might be raised:

Copying blob acab339ca1e8 done
ERRO[0002] Error while applying layer: ApplyLayer exit status 1 stdout:  stderr: potentially insufficient UIDs or GIDs available in user namespace (requested 0:12 for /var/spool/mail): Check /etc/subuid and /etc/subgid: lchown /var/spool/mail: invalid argument
Error: writing blob: adding layer with blob "sha256:ee0cde9de8a68f171a8c03b0e9954abf18576947e2f3187e84d8c31ccd8f6a09": ApplyLayer exit status 1 stdout:  stderr: potentially insufficient UIDs or GIDs available in user namespace (requested 0:12 for /var/spool/mail): Check /etc/subuid and /etc/subgid: lchown /var/spool/mail: invalid argument

Please refer to this blog post for further configuration information.

THANKS!

Many Thanks to @afbjorklund for a great discussion during the first revision of this container image that resulted in moving from using bash to using C, and the ensuing changes to the Containerfile.

Also many thanks to @mairin for the awesome ASCII art!