I work as system administrator for a company and I found there is a server that run Ubuntu server 14.04, and MySQL server listener port is 83306.
How can I set up net.ipv4.ip_local_port_range higher than 65535?
I attach to this post a screenshot of client connection mysqlworkbench.
And I also did a telnet on this port in Windows.
2 Answers
Port numbers above 65535 not only violate the TCP standard, they're literally impossible because the TCP package header field for the port number can only hold numbers between 0 and 65535 (i. e. a 16-bit unsigned integer).
The TCP protocol only permits ports between 1 and 65534, by its specification. To try and force otherwise is to be noncompliant with the TCP protocol; it also is impossible to do because of the reasons David mentioned in their answer, it can only hold numbers between 0 and 65534, due to being a 16 bit unsigned integer.
Just get a random number generator, and generate a random port above 50000 but below 65534, and use that number. Don't go breaking the TCP protocol just because you want to.
