01-10-2017
Can I assume that you are publishing tnsnames.ora so that anyone can read it? If so, why are you wanting to set up a listener on a new port?
The Oracle listener can support connections to multiple databases on the same host, all using the default port 1521. The database is coded in the connection request from the client whether you use the default port or any other port, unless your listener has a 'default if not specified' type definition. It would seem far better to use the listener and add connection details for each database. That way, the client never needs to worry about finding out which port to connect on, it just specifies the database name.
What am I missing here? If you are after hardening your server so that an intruder doesn't know which port to attack, then you have the same problem for your clients in that they will have to have a way to find out.
Can you explain the reasons why you want multiple listening processes? After the connection is established, the listener keeps out the way of the communication, so it's not a bottleneck to performance.
Thanks, in advance,
Robin
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LEARN ABOUT DEBIAN
valgrind-listener
VALGRIND(1) Release 3.7.0 VALGRIND(1)
NAME
valgrind-listener - a simple listener program for valgrind log redirection
SYNOPSIS
valgrind-listener [--exit-at-zero|-e] [port-number]
DESCRIPTION
valgrind-listener is a tool to be used in conjunction with Valgrind's ability to redirect its commentary output to a network socket (by
means of the --log-socket option).
valgrind-listener accepts connections on the specified port and copies whatever it is sent to stdout. It can accept simultaneous
connections from up to 50 Valgrinded processes. In front of each line of output it prints the current number of active connections in round
brackets.
port-number changes the port on which to listen for connections (default is 1500). It must be between 1024 and 65535. The same restriction
applies to port numbers specified by the --log-socket option to Valgrind itself.
Please note that killing the listener doesn't actually kill the processes sending data to it.
OPTIONS
-h --help
Show the help message.
-e --exit-at-zero
Causes the listener to exit when the number of connections falls back to zero (the default is to keep listening forever).
SEE ALSO
valgrind(1), $INSTALL/share/doc/valgrind/html/index.html or http://www.valgrind.org/docs/manual/index.html.
AUTHOR
The Valgrind developers.
This manual page was written by Cristian Greco <cristian@regolo.cc> and the Valgrind developers.
Release 3.7.0 06/05/2012 VALGRIND(1)