Oracle Distributed Systems

SQL*Net/Net8 Client Configuration

The sqlnet.orafile on a client machine contains parameters that govern the client’s behavior. The attributes that can be modified fall into five categories:

• Dead connection detection

• Tracing and logging

• Default domains

• Oracle Names parameters

• Other optional parameters

These attributes are described in the sections that follow.

Dead Connection Detection

SQL*Net/Net8 can automaticallydetect and terminate connections that are no longer valid. This feature is particularly useful for environments in which the clients are PCs, because users may reboot their PCs or otherwise terminate their sessions without logging out of the database. Rebooting a PC does not in and of itself cause the corresponding database session to terminate, because the underlying transport, such as TCP/IP, does not recognize it as such. The worst-case scenario is that the user reboots his PC while he has a lock on a table! Although you can assign a profile to your users that limits connect time and idle time, you usually have to set these limits high enough to accommodate users who want to go out to lunch without logging out of the application (e.g., several hours).

You can use dead connection detection to search and destroy invalid connections every 10 minutes or so. To do so, you must specify the optional parameter SQLNET.EXPIRE_TIME in the sqlnet.ora file. The number you specify is the frequency in minutes with which SQL*Net/Net8 probes connections to confirm their validity. Sessions that ...