Some users who connect to a busy Virtual Server have connections reset by the BIG-IP system. Pool member resources are NOT a factor in this behavior…

The "Connection Limit" setting on a virtual server defines the maximum number of concurrent connections it can handle. If this limit is reached on a busy virtual server, the BIG-IP system will, by default, reset any new connection attempts. Since the problem states pool member resources are not a factor, a misconfigured (too low) connection limit on the BIG-IP itself is a direct and likely cause for the observed connection resets during peak traffic.

A. The Connection Rate Limit is set too high: A high connection rate limit would allow more new connections per second, which is the opposite of what would cause resets on a busy system.

B. The server SSL Profile has NOT been reconfigured.: While an SSL profile issue can cause connection failures, it is not directly tied to the server being "busy" or the number of concurrent connections.

D. The Rewrite Profile has NOT been configured.: A rewrite profile modifies URI paths. Its absence would not cause connection resets based on the number of concurrent connections.

- F5 Networks. (2021). BIG-IP Local Traffic Manager: Concepts. Chapter: "Virtual Servers". Section: "Virtual server settings". The documentation specifies that the Connection Limit setting "specifies a maximum number of concurrent connections allowed for a virtual server. The default value of 0 (zero) specifies that there is no limit."

- F5 Support. (2020). K7543: The BIG-IP LTM can be configured to limit the number of concurrent connections to a virtual server. This article explicitly states, "When the connection limit is reached, the BIG-IP system resets subsequent TCP connection requests to the virtual server."