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February 28, 2026

8,600+ CELEBRATED $100 MILLION RAISED!

A10 X-forwarded-for [CONFIRMED • PICK]

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.

X-Forwarded-For: <client>, <proxy1>, <proxy2> a10 x-forwarded-for

If a backend server receives requests from multiple clients over the same persistent connection from the A10, the XFF header will change per request . Your backend application code must be designed to parse the XFF header on every HTTP request, not just at the TCP connection establishment. Java HttpServletRequest.getRemoteAddr() will still return the A10’s IP; you must explicitly call getHeader("X-Forwarded-For") . Blindly trusting the first XFF value you see is a common and dangerous anti-pattern. When a client connects to an A10 VIP