Wednesday, May 23, 2007
ora files
Oracle uses three files for it's network configurations-
Listener.ora
SQLNET.ORA
TNSNAMES.ORA
I will not go into listener.ora as that is used for server installations.
For a client installation or for connectivity issues, it is important to understand what the other two do. Simply put, SQLNET.ORA is the network configuration file and the TNSNAMES.ORA maps service names to connect descriptors. What does that mean ? Let's say I wish to connect to Oracle Service S which is running on Server A, Port P. I would use the TNSNAMES.ORA file to set it up, that is to say, when I call Service S, Oracle has to know which server and port it has to look for, right ? This "mapping" is defined in TNSNAMES.ORA.
The SQLNET.ORA file can be used to setup authentication, logging and tracing, lookups for resolving service names etc. For example, if you wish to setup the amount of time that the client tries to connect to a service before giving up, this would be the place to do it.
These files are generally in ORACLE_HOME\network\admin folder .
Secondly, when you are not able to connect to a service, a start point to check what is going on is to use TNSPING - a utility that you can use to check connectivity to the service (similar to PING).
Listener.ora
SQLNET.ORA
TNSNAMES.ORA
I will not go into listener.ora as that is used for server installations.
For a client installation or for connectivity issues, it is important to understand what the other two do. Simply put, SQLNET.ORA is the network configuration file and the TNSNAMES.ORA maps service names to connect descriptors. What does that mean ? Let's say I wish to connect to Oracle Service S which is running on Server A, Port P. I would use the TNSNAMES.ORA file to set it up, that is to say, when I call Service S, Oracle has to know which server and port it has to look for, right ? This "mapping" is defined in TNSNAMES.ORA.
The SQLNET.ORA file can be used to setup authentication, logging and tracing, lookups for resolving service names etc. For example, if you wish to setup the amount of time that the client tries to connect to a service before giving up, this would be the place to do it.
These files are generally in ORACLE_HOME\network\admin folder .
Secondly, when you are not able to connect to a service, a start point to check what is going on is to use TNSPING - a utility that you can use to check connectivity to the service (similar to PING).
# posted by NDR @ 8:43 PM 
