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Top Forums Shell Programming and Scripting Check unused ports in a given range and assign an open one Post 302989218 by rbatte1 on Tuesday 10th of January 2017 05:10:00 AM
Old 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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OCF_HEARTBEAT_ORALSN(7) 					OCF resource agents					   OCF_HEARTBEAT_ORALSN(7)

NAME
ocf_heartbeat_oralsnr - Manages an Oracle TNS listener SYNOPSIS
oralsnr [start | stop | status | monitor | meta-data | validate-all] DESCRIPTION
Resource script for Oracle Listener. It manages an Oracle Listener instance as an HA resource. SUPPORTED PARAMETERS
sid The Oracle SID (aka ORACLE_SID). Necessary for the monitor op, i.e. to do tnsping SID. (unique, required, string, no default) home The Oracle home directory (aka ORACLE_HOME). If not specified, then the SID should be listed in /etc/oratab. (optional, string, no default) user Run the listener as this user. (optional, string, no default) listener Listener instance to be started (as defined in listener.ora). Defaults to LISTENER. (unique, optional, string, no default) SUPPORTED ACTIONS
This resource agent supports the following actions (operations): start Starts the resource. Suggested minimum timeout: 120. stop Stops the resource. Suggested minimum timeout: 120. status Performs a status check. Suggested minimum timeout: 60. monitor Performs a detailed status check. Suggested minimum timeout: 30. Suggested interval: 10. validate-all Performs a validation of the resource configuration. Suggested minimum timeout: 5. meta-data Retrieves resource agent metadata (internal use only). Suggested minimum timeout: 5. methods Suggested minimum timeout: 5. EXAMPLE
The following is an example configuration for a oralsnr resource using the crm(8) shell: primitive p_oralsnr ocf:heartbeat:oralsnr params sid=string op monitor depth="0" timeout="30" interval="10" SEE ALSO
http://www.linux-ha.org/wiki/oralsnr_(resource_agent) AUTHOR
Linux-HA contributors (see the resource agent source for information about individual authors) resource-agents UNKNOWN 03/09/2014 OCF_HEARTBEAT_ORALSN(7)
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