How I Resolved ORA-03135: connection lost contact

Hunter Holley

User_2025-09-18-22-40-19-186

Hey, Great job,

Please tell me on which basis we need to changed the values with trace output. You changed the value of SQLNET.EXPIRE_TIME =5 in sqlnet.ora in database server, Please let me know on what basis we need to select 5 and please give me brief of this parameter SQLNET.EXPIRE_TIME and whether its 5 seconds or minutes.

Please explain me as an help.

Thanks is Advance.

Mohammed

 

kareardo-Oracle

Hey, Great job,

Please tell me on which basis we need to changed the values with trace output. You changed the value of SQLNET.EXPIRE_TIME =5 in sqlnet.ora in database server, Please let me know on what basis we need to select 5 and please give me brief of this parameter SQLNET.EXPIRE_TIME and whether its 5 seconds or minutes.

Please explain me as an help.

Thanks is Advance.

Mohammed

 

 You can find out more about any Oracle Net parameter in the Oracle Net Services Reference Guide.

5.2.28 SQLNET.EXPIRE_TIME

Purpose

Use parameter SQLNET.EXPIRE_TIME to specify a time interval, in minutes, to send a probe to verify that client/server connections are active. Setting a value greater than 0 ensures that connections are not left open indefinitely, due to an abnormal client termination. If the probe finds a terminated connection, or a connection that is no longer in use, it returns an error, causing the server process to exit. This parameter is primarily intended for the database server, which typically handles multiple connections at any one time.

Limitations on using this terminated connection detection feature are:

• It is not allowed on bequeathed connections.

• Though very small, a probe packet generates additional traffic that may downgrade network performance.

• Depending on which operating system is in use, the server may need to perform additional processing to distinguish the connection probing event from other events that occur. This can also result in degraded network performance.

Default

0
	
	

Minimum Value

0
	
	

Recommended Value

10
	
	

Example

SQLNET.EXPIRE_TIME=10
	
	

This parameter controls the interval in which the Server process will send out what are called Dead Connection Detection (DCD) packets to see if the Client is still there.  The appendix refers to this parameter as the TNS Timeout value:

TNS Time Out Value

<a id="sthref693" name="sthref693"></a>SQLNET.EXPIRE_TIME

Use to specify a specify the time interval, in minutes, to send a probe to verify that client/server connections are active. Setting a value greater than 0 ensures that connections are not left open indefinitely, due to an abnormal client termination. If the probe finds a terminated connection, or a connection that is no longer in use, it returns an error, causing the server process to exit. This setting is intended for the database server, which typically handles multiple connections at any one time. Limitations on using this terminated connection detection feature are: It is not allowed on bequeathed connections. Though very small, a probe packet generates additional traffic that may downgrade network performance. Depending on which operating system is in use, the server may need to perform additional processing to distinguish the connection probing event from other events that occur. This can also result in downgrading network performance.

Keep in mind that it is the Server process that sends out this packet, the Client does not.  Also, the first DCD packet will be sent out after twice this setting (due to some timer issues).  So if you use this to keep an idle connection open through a firewall, you should set this interval to half the idle timeout setting on the firewall.