SAS (Siebel Analytics Server)

Background
In an environment where the Siebel Analytics Server (SAS) connects to an Oracle 9i database, the SAS stops responding and may also crash after some time, in any one of the following ways:
Siebel Analytics Web starts hanging after a few hours and new users are unable to login into Siebel Analytics Web.
Administrators cannot log into the Siebel Analytics Administration Tool in online mode.
The Siebel Analytics Server may crash. This is a random crash and happens when multiple threads are doing OCILogon() simultaneously. It is not always reproducible; you may run the test case multiple times before the crash occurs.
The only workaround is to restart the Siebel Analytics service.
 
This behavior is related to Oracle 9i versions and not to Siebel Analytics. Therefore, this behavior is observed on all versions of Siebel Analytics where Oracle client 9i is used.
 
Oracle has identified an issue with the Oracle OCI client which may cause the SAS to crash; the Oracle client which resides on the same machine as the SAS is unable to handle a number of concurrent threads to the backend Oracle database. Oracle has isolated the problem within the network layer of the client, and this behavior is fixed in the Oracle client 10g.

Solution
To resolve this behavior, here are the different options:
Use Oracle client version 10g on the SAS machine.
 NOTE: Oracle supports Oracle client 10g with Oracle 9.2.0x RDBMS. Also note that Oci 10g has not been certified with Analytics 7.7.x, only with Analytics 7.8 but this should not cause any issues, although Oracle recommends that you upgrade Analytics to the latest 7.8 release at your earliest convenience.
Use Oracle client version 8.1.7.4 with its latest fix pack on the SAS machine (8.1.7.4.6 for Windows, and 8.1.7.4 for UNIX).
If neither of the options 1 or 2 is feasible, and you are using Oracle client version 9i, use the following workaround:
In the Oracle database client version that has the behavior, explicitly set the following parameter in the sqlnet.ora file, located in the %ORACLE HOME%\ora92\network\admin directory:
 
SQLNET.AUTHENTICATION_SERVICES=(NONE)
 
If this entry does not exist in the sqlnet.ora file, you will need to create it. Please ensure that there are no typographical errors in the sqlnet.ora file after you have added the specified parameter setting. This workaround does not have a performance impact.
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