I am bit puzzled about how TCP load balancer works, in particular AWS ELB. By looking at AWS ELB doc:
For TCP traffic, the load balancer selects a target using a flow hash algorithm based on the protocol, source IP address, source port, destination IP address, destination port, and TCP sequence number. The TCP connections from a client have different source ports and sequence numbers, and can be routed to different targets. Each individual TCP connection is routed to a single target for the life of the connection.
This confuses me. I assume/expect that a TCP connection persists to the same target for the duration of it. However (!) if the hash algorithm takes in account also the TCP sequence number - which is going to change for every tcp packet round-trip - then such connection is (wrongly) routed to other targets after every tcp packet round-trip.. Please help.
