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Troubleshooting WAF, CDN, and Load balancer

 Troubleshooting issues involving a Web Application Firewall (WAF), Content Delivery Network (CDN), and Load Balancer (LB) can be complex. Here is a step-by-step guide, including testing methods and relevant commands to isolate problems at each level. ### Step 1: Check Basic Connectivity 1. **Ping the Website**:    ```sh    ping example.com    ``` 2. **Check DNS Resolution**:    ```sh    nslookup example.com    ``` ### Step 2: Verify Load Balancer 1. **Direct Access to Load Balancer**:    Modify `/etc/hosts` to bypass CDN and WAF, pointing directly to the load balancer’s IP.    ```sh    sudo nano /etc/hosts    ```    Add the line:    ```    LB_IP example.com    ```     2. **Test HTTP Response**:    ```sh    curl -I http://example.com    ```    Check headers and status code to verify the load balancer is responding correctly. 3. **Check Load Balancer Logs**:    Access logs on the load balancer to see if requests are hitting it and how they are being routed.    ```sh    tail -f /var/log/