What is the difference between a listener.ora and tnsnames.ora files

The net service name thus becomes a most likely shorter and more readable alias for the somewhat cumbersome net service name. In the following example, the? The sqlnet. Here is an example of an sqlnet. By default, the listener. Lister is Network Service to establish connection between client machine and server. Lister are stored at server side. In most cases only one listener is required.

This listener is configured via a listener. This file includes the listener process configuration, mainly: Host for which it listens, protocol and port, list of SIDs for which the process can establish a connection. Furthermore, if you are connecting to the database on the server computer, and it is the default database, you do not need to tell where you are going to connect when you are the client.

For default Database you do not even need to have a listener when you are the server and the client both. The tnsnames. When it finds a match it reads the name of the server where it should connect to ,the protocol it should use TCP and the port on which a listener is listening default When it finds a match it goes to the relevant server and knocks on the port where the listener is waiting to hear incoming calls.

If it matches, you are given an entry for the database to connect and a session is created for you. So, tnsnames. The client first tries the first or second protocol address at random, then tries protocol addresses three and four sequentially. Example Multiple Address Lists in tnsnames. Oracle Net Manager supports only the creation of one protocol address list for a connect descriptor.

The parameter is added manually to the file. The following is an example of the syntax:. Refer to Oracle Database Reference for additional information.

When a connect descriptor in a tnsnames. Example illustrates failover of multiple Oracle Connection Manager protocol addresses. The client is instructed to connect to the protocol address of the first Oracle Connection Manager, as indicated by:.

The first Oracle Connection Manager is instructed to connect to the first protocol address of another Oracle Connection Manager. If the first protocol address fails, then it tries the second protocol address. This sequence is specified with the following configuration:. Example illustrates client load balancing among two Oracle Connection Managers and two protocol addresses:. Example Client Load Balancing in tnsnames.

These parameters are described in this section. The protocol address section of the tnsnames. To allow the caller to detect a terminated remote server, typically it takes 2 hours or more to notice. Operating system TCP configurables, which vary by platform, define the actual keepalive timing details.

When you set the parameter to on , yes , or true , Oracle Net fails over at connect time to a different address if the first protocol address fails. When you set the parameter to off , no , or false , Oracle Net tries one protocol address.

When you set the parameter to on , yes , or true , Oracle Net goes through the list of addresses in a random sequence, balancing the load on the various listener or Oracle Connection Manager protocol addresses.

When you set the parameter to off , no , or false , Oracle Net tries the protocol addresses sequentially until one succeeds. The default value for this parameter is specific to the operating system. The default for the Linux 2. To setup network, we must have listener running on the server and tnsnames.

Configure listener. Configure tnsnames. The listerner. Below is the default listener configuration. Whenever you make changes to the listener. In multi-tenant architecture, each PDB can be considered as an individual databases.