When a domain is blocked, the website may become inaccessible in mainland China. Redirect systems (or domain redirect solutions) use technical methods to redirect user requests from a blocked domain to an accessible domain or server, restoring access. Below are several common redirect systems or solutions for blocked domains, covering mainstream technologies and tools suitable for different scenarios. Carefully evaluate compliance risks and technical limitations based on your situation. Here are the specific technical solutions and their analysis:

1. 30x Redirects: Traffic Redirection with Risks #

• Description: Uses HTTP status codes (301 permanent redirect or 302 temporary redirect) to guide users from a blocked domain to a new or unblocked backup domain.
• Technical Principle:
  • 301 Redirect: Permanent redirect, transferring the original domain’s SEO weight to the new domain, SEO-friendly.
  • 302 Redirect: Temporary redirect, suitable for short-term maintenance or testing.
• Implementation:
  • Server-Side Configuration:
    • Nginx: Add redirect rules in the configuration file, e.g.:

      server {
          listen 80;
          server_name old-blocked-domain.com;
          return 301 $scheme://new-domain.com$request_uri;
      }
      

    • Apache: Add to the .htaccess file:

      Redirect 301 / http://new-domain.com/
      

  • DNS Provider: Some DNS providers (e.g., GoDaddy, Namecheap) support simple domain redirect settings.
• Use Case: Suitable for websites that have switched to a new domain and want to retain traffic or SEO weight from the old domain.
• Risks and Case Study:
  • Detection Risk: The firewall may detect redirect behavior, and if the new domain lacks ICP filing or contains non-compliant content, it may also be blocked.
  • SEO Loss: Chained redirects (e.g., A→B→C) can reduce search engine weight.
  • Case Study: A website used a 301 redirect, but the new domain was blocked again shortly after due to unaddressed sensitive content from the original site.
• Advantages: Simple setup, SEO-friendly (301 transfers weight), no additional tools required.
• Disadvantages: Requires a pre-prepared unblocked new domain; if the new domain is blocked, the process must be repeated.

2. CDN-Based Redirect System #

• Description: Uses a Content Delivery Network (CDN)’s reverse proxy to redirect traffic from a blocked domain to an accessible server or backup domain via CDN nodes.
• Risks and Case Study:
  • Node Risk: If CDN nodes lack ICP filing or host non-compliant content, the CDN provider may be required to disable the nodes.
  • Case Study: A website using an overseas CDN experienced service disruptions when its nodes were blocked.
• Common Providers:
  • Cloudflare: Set up URL forwarding via Page Rules or use reverse proxy to hide the original server IP.
  • Alibaba Cloud CDN/Tencent Cloud CDN: Support domestic nodes, configure domain resolution to the CDN’s CNAME record.
  • Akamai: Ideal for large enterprises with strong defense capabilities.
• Implementation:
  1. Register for a CDN service and add the blocked domain.
  2. Update DNS resolution to point the domain to the CDN’s IP or CNAME.
  3. Configure redirect rules or reverse proxy in the CDN dashboard to an unblocked server.
• Use Case: Suitable for retaining the original domain without frequent changes.
• Advantages: No need to change domains, CDNs can accelerate access and defend against attacks, some providers offer free plans.
• Disadvantages: Free CDN nodes may be detected by the GFW; domestic CDNs require ICP filing.

3. DNS Smart Resolution Redirect System #

• Description: Uses intelligent DNS resolution to redirect domestic users to an unblocked server or domain based on their geographic location or network environment, while overseas users access the original server.
• Risks and Case Study:
  • DNS Pollution: Authorities may tamper with DNS resolution, redirecting users to blank or warning pages.
  • ICP Filing Requirement: Resolving unfiled domains to overseas IPs long-term may trigger regulatory scrutiny.
  • Case Study: A website resolved its domain to an overseas CDN, but domestic users still couldn’t access it due to GFW interference with DNS queries.
• Common Providers:
  • DNSPod (Tencent Cloud): Supports line-based distribution, resolving domestic users to domestic servers and overseas users to the original server.
  • Alibaba Cloud DNS: Offers smart resolution based on IP regions.
  • Cloudflare DNS: Combines GeoDNS for regional redirects.
• Implementation:
  1. Add the blocked domain to the DNS provider.
  2. Configure smart resolution rules, e.g., domestic users resolve to a new domain/IP, overseas users to the original IP.
  3. Pair with a CDN or backup server to ensure stable access post-redirect.
• Use Case: Websites with both domestic and overseas users, needing separate access paths.
• Advantages: High flexibility, precise traffic allocation, minimal SEO impact.
• Disadvantages: Slightly complex setup, requires maintaining multiple servers or domains; domestic DNS services may require ICP filing.

4. Reverse Proxy Redirect System #

• Description: Uses a reverse proxy server (e.g., Nginx, HAProxy) to forward user requests from a blocked domain to an unblocked server or domain, hiding the original server’s IP.
• Implementation:
  • Deploy an unblocked proxy server (preferably a domestic filed server or Hong Kong server).
  • Configure Nginx reverse proxy, e.g.:

    server {
        listen 80;
        server_name blocked-domain.com;
        location / {
            proxy_pass http://new-server-ip-or-domain.com;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
        }
    }
    

  • Update DNS to resolve the blocked domain to the proxy server’s IP.
• Use Case: Suitable for avoiding domain changes while quickly restoring domestic access.
• Advantages: Flexible implementation, customizable redirect logic, no client-side configuration needed.
• Disadvantages: Proxy server requires high availability, higher costs; if the proxy IP is blocked, it needs replacement.

5. VPN or Proxy Redirect System (Client-Side) #

• Description: Users configure a VPN or proxy on their browser or app to bypass GFW restrictions and access the blocked domain directly. Websites typically guide users to implement this.
• Risks and Case Study:
  • Stability Issues: Proxy servers may be blocked or overloaded, causing unstable access.
  • Legal Risks: Using proxies/VPNs to access restricted content may violate laws in some regions.
• Implementation:
  • The website provides VPN/proxy setup tutorials, recommending reliable services (e.g., NordVPN, ExpressVPN).
  • Set up a proprietary proxy service (e.g., Shadowsocks, V2Ray) and provide client configuration files.
  • Display a blocked domain notice on the site, guiding users to download a VPN or switch to a backup domain.
• Use Case: Suitable for websites unable to quickly change domains or servers, needing short-term user access restoration.
• Advantages: No server-side changes required, ideal for webmasters with limited technical capabilities.
• Disadvantages: Relies on user configuration, poor user experience; VPN services may be blocked, increasing user costs.

6. Domestic ICP Filing Redirect System #

• Description: Migrate the website to a domestic server with ICP filing, using compliant domestic domains and servers to avoid GFW restrictions entirely. A redirect system can be used during the transition to redirect the blocked domain to the filed domain.
• Implementation:
  1. Purchase a domestic server (e.g., Alibaba Cloud, Tencent Cloud).
  2. Complete ICP filing and migrate website data.
  3. Configure a 301 redirect from the blocked domain to the new filed domain.
  4. Optionally use a CDN to accelerate domestic access.
• Use Case: Long-term website operations prioritizing compliance and stability.
• Advantages: High compliance, minimal risk of blocking; fast domestic access.
• Disadvantages: Long filing process (7-20 days), requires removing sensitive content; unsuitable for websites targeting overseas users.

7. Professional Redirect Services: Convenient but Choose Carefully #

• Technical Principle: Providers offer 301 redirect services, resolving the blocked domain to their nodes, which then redirect to the new domain.
• Operation: Users resolve the blocked domain to the provider’s nodes, and the provider handles redirect configuration.
• Risks and Case Study:
  • Compliance Risk: If the provider’s nodes lack ICP filing or host non-compliant content, they may be blocked.
  • Case Study: A provider’s nodes were blocked, causing redirect failures for many user domains.
• Use Case: Websites needing quick access restoration with fully compliant content.

Comparison and Selection Guide #

Notes #

• Check Domain Status: Use tools (e.g., www.feige301.com or GreatFire.org) to confirm if the domain is blocked and rule out other issues.
• Avoid Sensitive Content: Regardless of the redirect system, avoid political, adult, or gambling content to prevent the new domain or IP from being blocked.
• Notify Users: Inform users of the new domain or access method via email, social media, or site announcements.
• Backup Data: Back up the website and database before implementing redirects to prevent data loss due to configuration errors.
• Monitor Performance: After redirecting, use Google Analytics or Baidu Analytics to monitor traffic changes and ensure the redirect is effective.