Docker新手求助：容器运行正常但浏览器无法访问服务

Hey there! Let's walk through why your mywebapp container isn't loading in the browser and get it fixed. I notice a couple of key mismatches in your setup that are likely causing the issue, plus some quick checks to rule out other factors.

1. Fix the Nginx Configuration & Port Mismatch #

Your current Dockerfile exposes port 8000, but the default Nginx image listens on port 80 out of the box. On top of that, you're copying your code to /app, but Nginx doesn't know to serve files from there—it uses /usr/share/nginx/html by default. Here's how to fix both problems:

Step 1: Update Your Dockerfile #

Replace your existing Dockerfile with this version, which adds a custom Nginx config to set the correct port and serve directory:

FROM nginx:latest
# Create app directory and copy your source code
RUN mkdir /app
COPY . /app
# Replace Nginx's default config with our custom one
COPY nginx.conf /etc/nginx/conf.d/default.conf
# Expose the port we configured Nginx to listen on
EXPOSE 8000

Step 2: Create the Custom Nginx Config #

Make a file named nginx.conf in your source directory with this content:

server {
    listen 8000;
    server_name localhost;

    # Point Nginx to your app's files
    root /app;
    index index.html index.htm;

    location / {
        try_files $uri $uri/ =404;
    }
}

2. Rebuild and Rerun the Container #

Now rebuild your image with the fixed setup:

docker build -t mywebapp:v2 .

Then stop the old container (if it's still running) and start the new one:

# Find the old container ID
docker ps
# Stop it
docker stop <container-id>
# Run the updated image
docker run -d -p 8000:8000 mywebapp:v2

3. Quick Checks for Persisting Issues #

If it's still not working, run through these troubleshooting steps:

• Check container logs for Nginx errors:

  docker logs <container-id>
  

  Look for lines mentioning "failed to start" or "invalid config"—that'll tell you if Nginx isn't loading correctly.
• Verify Nginx is listening on port 8000 inside the container:

  docker exec -it <container-id> bash
  # Inside the container, run:
  netstat -tulpn | grep nginx
  

  You should see a line showing 0.0.0.0:8000.
• Test connectivity directly from the host:
  Skip the browser and test with curl to isolate the issue:

  curl http://192.168.13.135:8000
  

  If you get a 404, make sure you have an index.html file in your source directory (Nginx needs a default file to serve).
• Check host firewall settings:
  Ensure port 8000 is open on your host machine. For example, on Ubuntu/Debian you can run:

  sudo ufw allow 8000
  

内容的提问来源于stack exchange，提问作者v.samraksh