Nginx Rewrite规则不生效求助：短域名转FQDN配置排查

Let's break down why your rewrite rule isn't taking effect and fix it with actionable steps:

1. First, Confirm the Request Is Hitting the Correct server Block #

Nginx matches requests to server blocks based on the Host header and listen directive. If your request is routed to a different block (like a default server), your rewrite will never run.

• Check for default server conflicts: If another server block uses listen 80 default_server, it will take priority. Add default_server to your listen directive to ensure this block catches matching requests:

  server {
      listen 80 default_server;
      server_name foo foo.bar.com;
      # ... rest of your config
  }
  

• Verify with logs: Check your Nginx access log (typically /var/log/nginx/access.log) to confirm the incoming request's Host header matches foo or foo.bar.com.
• Quick test: Temporarily replace your rewrite rule with return 200 "Block Test"; and restart Nginx. If you see this message when accessing http://foo or http://foo.bar.com, the block is being hit.

2. Use return Instead of rewrite for Redirects #

return is more efficient and reliable for permanent redirects than rewrite, and it can preserve the original request URI if needed:

server {
    listen 80 default_server;
    server_name foo foo.bar.com;
    rewrite_log on;
    # Redirect to HTTPS while keeping the original request path
    return 301 https://foo.bar.com$request_uri;
    # If you want to redirect *only* to the root, use:
    # return 301 https://foo.bar.com/;
    include includes/web-site;
    include includes/files-site;
}

3. Check for Conflicts in Included Files #

While your rewrite runs before the include statements, it's worth verifying that the included files don't have directives that could interfere. Open includes/web-site and includes/files-site to ensure there are no rewrite or return lines that might override your redirect.

4. Fix SSL Block Syntax Errors #

Your config snippet cuts off at ssl_certifica...—syntax errors in the SSL block (like a missing ssl_certificate_key line) will prevent Nginx from reloading your new config. Validate your full config with:

nginx -t

Fix any errors (e.g., add ssl_certificate_key foobar.key; to match your certificate file) before restarting Nginx.

5. Check the Rewrite Log #

Since you enabled rewrite_log on;, look for lines starting with rewritten request: in your error log (usually /var/log/nginx/error.log). If you don't see these lines, the request isn't hitting your server block. If you do see them, your browser might be caching an old response—test with curl -v http://foo to view the raw redirect.

内容的提问来源于stack exchange，提问作者tyon