Assuming infinite performance from hardware, can a Linux box support >65536 open TCP connections?
I understand that the number of ephemeral ports (<65536) limits the number of connections from one local IP to one port on one remote IP.
The tuple (local ip, local port, remote ip, remote port) is what uniquely defines a TCP connection; does this imply that more than 65K connections can be supported if more than one of these parameters are free. e.g. connections to a single port number on multiple remote hosts from multiple local IPs.
Is there another 16 bit limit in the system? Number of file descriptors perhaps?