IBM® data server clients
and non-Java data server drivers that have a DB2 Connect™ license can now access a DB2® for z/OS® Sysplex
directly. Licensed clients are no longer required to go through a
middle-tier IBM DB2 Connect 9.7 server
to use Sysplex capabilities.
The following Sysplex capabilities are now available
in IBM data server clients and
the non-Java data server drivers ( IBM Data
Server Driver Package and IBM Data
Server Driver for ODBC and CLI):
- Transaction-level load balancing
- Prior to the introduction of this feature, client applications
that required transaction-level workload balancing had to go through
a IBM DB2 Connect 9.7 server.
Now, support for distributing transactions among members within a DB2 data-sharing group is available
in the client, so applications accessing a DB2 for z/OS Sysplex
no longer have to go through a IBM DB2 Connect 9.7 server.
- Automatic client reroute with seamless failover for CLI and .NET
applications
- When connectivity to a member within a Sysplex
is lost, the automatic client reroute feature allows the client to
recover from the failure by attempting to reconnect to the database
through any member of the Sysplex. Prior to the introduction of this
feature, when a CLI or .NET application reestablished a database connection,
an error (typically, SQL30081N) was always returned to the application
to indicate that the failed transaction had been rolled back. Now,
CLI or .NET applications that encounter a connectivity failure on
the first SQL operation in a transaction are allowed to replay the
failed SQL operation as part of automatic client reroute processing.
If the connection is successful, no error is reported to the application,
and the transaction is not rolled back. The connectivity failure and
subsequent recovery are hidden from the application.
Clients can
perform failover based on a client-specified server list (known as
the alternate server list) or the server list that is returned by
the database server during the last connect.
Some restrictions
apply to seamless failover support.
- Client-side XA support available for some transaction managers
- Prior to the introduction of this feature, client-side XA support
for DB2 for z/OS was
not available, so non-Java client applications had to go through a IBM DB2 Connect 9.7 server
to obtain XA support for DB2 for z/OS.
Now, XA support for DB2 for z/OS is
available in IBM data server
clients and non-Java data server drivers.
Sysplex workload balancing is also supported by the IBM Data Server
Driver for JDBC and SQLJ.
DB2 Version 9.7 for Linux, UNIX, and Windows