An upstream device, such as a load balancer or router within a server farm, may perform sticky routing of session requests to the servers handling those sessions by generating unique ID(s) identifying how requests may be routed through the server farm. Upstream devices through which travels a request that is not associated with a session on a server of the server farm may generate one or more unique IDs identifying how the request is routed through the server farm. The server handling the request may form a session ID and return that session ID and the unique ID(s) to the client that originated the new request and session. Clients may then send the session ID and unique IDs with clients requests for that session. Upon receiving requests corresponding to established sessions, the upstream devices may then identify routing information from the unique ID(s) and route the request accordingly.