108 lines
2.6 KiB
Markdown
108 lines
2.6 KiB
Markdown
|
# Create Images on The Fly
|
||
|
|
|
||
|
|
## Requirements
|
||
|
|
|
||
|
|
Have at least one image locally (run `podman image ls` to confirm).<br>
|
||
|
|
If you don't have images locally, run simply `podman pull nginx:alpine`.
|
||
|
|
|
||
|
|
## Objectives
|
||
|
|
|
||
|
|
1. Run a container using a web server image (e.g. httpd, nginx, ...)
|
||
|
|
- Bind container's port 80 to local port 80
|
||
|
|
- Run it in detached mode
|
||
|
|
- Name should nginx_container
|
||
|
|
2. Verify the web server runs and accessible
|
||
|
|
3. Create an HTML file with the following content and copy it to the container to the container to path where it will be accessed as an index file
|
||
|
|
|
||
|
|
```
|
||
|
|
<html>
|
||
|
|
<head>
|
||
|
|
<title>It's a me</title>
|
||
|
|
</head>
|
||
|
|
<body>
|
||
|
|
<h1>Mario</h1>
|
||
|
|
</body>
|
||
|
|
```
|
||
|
|
|
||
|
|
4. Create an image out of the running container and call it "nginx_mario"
|
||
|
|
5. Tag the container with "mario" tag
|
||
|
|
6. Remove the original container (container_nginx) and verify it was removed
|
||
|
|
7. Create a new container out of the image you've created (the same way as the original container)
|
||
|
|
8. Run `curl 127.0.0.1:80`. What do you see?
|
||
|
|
9. Run `podman diff` on the new image. Explain the output
|
||
|
|
|
||
|
|
## Solution
|
||
|
|
|
||
|
|
```
|
||
|
|
# Run the container
|
||
|
|
podman run --name nginx_container -d -p 80:80 nginx:alpine
|
||
|
|
|
||
|
|
# Verify web server is running
|
||
|
|
curl 127.0.0.1:80
|
||
|
|
# <!DOCTYPE html>
|
||
|
|
# <html>
|
||
|
|
# <head>
|
||
|
|
# <title>Welcome to nginx!</title>
|
||
|
|
|
||
|
|
# Create index.html file
|
||
|
|
cat <<EOT >>index.html
|
||
|
|
<html>
|
||
|
|
<head>
|
||
|
|
<title>It's a me</title>
|
||
|
|
</head>
|
||
|
|
<body>
|
||
|
|
<h1>Mario</h1>
|
||
|
|
</body>
|
||
|
|
EOT
|
||
|
|
|
||
|
|
# Copy index.html to the container
|
||
|
|
podman cp index.html nginx_container:/usr/share/nginx/html/index.html
|
||
|
|
|
||
|
|
# Create a new image out of the running container
|
||
|
|
podman commit nginx_container nginx_mario
|
||
|
|
|
||
|
|
# Tag the image
|
||
|
|
podman image ls
|
||
|
|
# localhost/nginx_mario latest dc7ed2343521 52 seconds ago 25 MB
|
||
|
|
podman tag dc7ed2343521 mario
|
||
|
|
|
||
|
|
# Remove the container
|
||
|
|
podman stop nginx_container
|
||
|
|
podman rm nginx_container
|
||
|
|
podman ps -a # no container 'nginx_container'
|
||
|
|
|
||
|
|
# Create a container out of the image
|
||
|
|
podman run -d -p 80:80 nginx_mario
|
||
|
|
|
||
|
|
# Check the container created from the new image
|
||
|
|
curl 127.0.0.1:80
|
||
|
|
#<html>
|
||
|
|
#<head>
|
||
|
|
#<title>It's a me</title>
|
||
|
|
#</head>
|
||
|
|
#<body>
|
||
|
|
#<h1>Mario</h1>
|
||
|
|
#</body>
|
||
|
|
|
||
|
|
# Run diff
|
||
|
|
podman diff nginx_mario
|
||
|
|
|
||
|
|
C /etc
|
||
|
|
C /etc/nginx/conf.d
|
||
|
|
C /etc/nginx/conf.d/default.conf
|
||
|
|
A /run/nginx.pid
|
||
|
|
C /usr/share/nginx/html
|
||
|
|
C /usr/share/nginx/html/index.html
|
||
|
|
C /var/cache/nginx
|
||
|
|
C /var
|
||
|
|
C /var/cache
|
||
|
|
A /var/cache/nginx/client_temp
|
||
|
|
A /var/cache/nginx/fastcgi_temp
|
||
|
|
A /var/cache/nginx/proxy_temp
|
||
|
|
A /var/cache/nginx/scgi_temp
|
||
|
|
A /var/cache/nginx/uwsgi_temp
|
||
|
|
|
||
|
|
# We've set new index.html which explains why it's changed (C)
|
||
|
|
# We also created the image while the web server is running, which explains all the files created under /var
|
||
|
|
```
|