A10 X-forwarded-for -

In the modern data center, the Application Delivery Controller (ADC) sits as the gatekeeper. A10 Networks’ Thunder series is a market leader in this space, performing tasks from server load balancing (SLB) and SSL offload to advanced L7 inspection.

However, by inserting itself between the client and the server, an ADC creates a classic networking paradox: a10 x-forwarded-for

When configured for L7 load balancing (HTTP mode), the A10 ADC rewrites the HTTP request headers before forwarding the packet to the real server. It typically appends the original client IP address to the existing XFF header. In the modern data center, the Application Delivery

When a client connects to an A10 VIP (Virtual IP), the A10 establishes a separate TCP connection to the backend server. From the server’s perspective, the source IP of every single packet is the A10’s own LAN IP—not the remote user. This breaks logging, geo-location, rate-limiting, and security rules. It typically appends the original client IP address

In the CLI:

X-Forwarded-For: <client>, <proxy1>, <proxy2>