Hey there! Let's work through your Nginx redirect/rewrite problems—this is a super common pain point, so I'll break down exact implementations, key pitfalls, and testing tips to get your rules working as expected.

1. Start with the return Directive (Preferred for Simple Redirects) #

The return directive is more efficient than rewrite for straightforward redirects, so use this first whenever possible. It supports both permanent (301) and temporary (302) redirects.

Example 1: Redirect an Entire Domain #

server {
    listen 80;
    server_name old.example.com;
    # Redirect all traffic to the new domain, preserving protocol and original path
    return 301 $scheme://new.example.com$request_uri;
}

Example 2: Redirect a Specific Path #

location /old-checkout {
    # Temporary redirect to the new checkout page
    return 302 /new-checkout;
}

• $scheme automatically uses http or https based on the incoming request
• $request_uri preserves the original path and query parameters (e.g., /old-path?foo=bar becomes /new-path?foo=bar)

2. Use rewrite for Complex Pattern Matching #

When you need regex-based matching (like dynamic URLs), use the rewrite directive. Its syntax is:

rewrite regex replacement [flag];

Example 1: Rewrite Dynamic Article URLs #

location /archive {
    # Match /archive/123 and redirect to /blog/post-123
    rewrite ^/archive/(\d+)$ /blog/post-$1 permanent;
}

Example 2: Rewrite URLs with Query Parameters #

location /shop {
    # Match /shop?product_id=456 and rewrite to /products/456
    rewrite ^/shop$ /products/$arg_product_id? last;
}

Key Flags to Know:

• permanent: Sends a 301 (permanent) redirect (cached by browsers)
• redirect: Sends a 302 (temporary) redirect
• last: Stops processing current rules and re-matches the new URI against all server/location blocks
• break: Stops processing all subsequent rules in the current location block

3. Why Your Rules Might Not Be Working (Common Pitfalls) #

If your redirects/rewrites aren’t taking effect, check these first:

• Wrong Configuration Block: Make sure your rules are in the correct server block (e.g., if using HTTPS, rules need to be in the listen 443 ssl block, not the listen 80 block).
• Regex Mistakes: Forgetting anchors (^ = start of string, $ = end of string) can cause over-matching or no matching at all. For example, rewrite /archive /blog will match any URL containing /archive, while ^/archive$ only matches the exact /archive path.
• Browser Caching: 301 redirects are cached aggressively by browsers. Test in incognito mode, clear your cache, or use curl to bypass browser caching.
• 未重载配置: After editing your Nginx config, run sudo nginx -t to validate syntax, then sudo nginx -s reload to apply changes. If nginx -t throws errors, your config won’t reload.
• Location Priority Conflicts: Nginx matches locations in this order:
  1. Exact matches (location = /path)
  2. Prefix matches with ^~
  3. Case-sensitive regex matches (~)
  4. Case-insensitive regex matches (~*)
  5. Regular prefix matches
     If a higher-priority location is handling your request, your rewrite/redirect rule won’t trigger.

4. Test Your Rules Effectively #

• Use curl to Debug: Run curl -v http://your-domain.com/old-path to see the full request/response cycle. Look for the Location header to confirm the redirect target.
• Check Nginx Logs: Review /var/log/nginx/access.log to see if your request is hitting the right location block, and /var/log/nginx/error.log for any syntax or runtime errors.

Full Working Example #

Here’s a complete config that handles domain redirects, path redirects, and dynamic rewrites:

server {
    listen 80;
    server_name old.example.com www.old.example.com;
    # Redirect HTTP traffic to HTTPS on the new domain
    return 301 https://new.example.com$request_uri;
}

server {
    listen 443 ssl;
    server_name new.example.com;

    # SSL certificate config (omitted for brevity)
    ssl_certificate /path/to/cert.pem;
    ssl_certificate_key /path/to/key.pem;

    # Exact path redirect
    location = /old-about {
        return 301 /about-us;
    }

    # Dynamic rewrite for blog posts
    location /legacy-blog {
        rewrite ^/legacy-blog/(\d+)-(\w+)$ /articles/$2?post_id=$1 permanent;
    }

    # Serve your main site content
    location / {
        root /var/www/your-site;
        index index.html index.php;
    }
}

内容的提问来源于stack exchange，提问作者edward.