The first phase in performing a port is to assess the magnitude of the work that will be involved. Doing this in an organized and detailed manner can help minimize schedule and budget overruns, and provides a clear roadmap for the full project.
Before starting the assessment phase, IBM customers should contact the Software Migration Project Office (SMPO) for free porting estimates, as well as access to a team of experts that can help with your port. You can contact the SMPO using the link above or by e-mail (db2mig@us.ibm.com).
The assessment begins by collecting information about both the source and target environments. This detailed information about the database and the application is used to determine the scope of the porting process, and is the main input for the port planning process. In addition to the information collected, a series of DB2 porting guides are available that will also help you understand the differences between other database systems and DB2, and the most common conversion issues that you might run into.
In order to perform a detailed assessment, you need to access the source system and query the database for important information (number of tables, indexes, stored procedures, and so on), as well as retrieve design information from someone familiar with the system. Often, you can retrieve information from the source system by using SQL scripts that query the system tables or by using a utility provided by the source DBMS vendor.
Another effective way of accumulating detailed information from the source DBMS is through the use of the extraction capabilities of porting and migration tools. For example, you can use the IBM Migration Toolkit (MTK)
to retrieve structural and object information from Oracle, Sybase, and SQL Server DBMSs.
Assessment items
The following is a list of some of the information that you will want to collect before planning your port. Keep in mind that this is just a partial list to get you thinking about the type of information you should collect.
Application overview
Primary function of the application
DBMSs currently supported by the application
DBMS that will be used to port from
Non-relational or proprietary DBMSs used
Application architecture (host, 2-tier Client-Server, n-tier, and more)
Application diagrams
Web technologies used (EJB, ASP, JSP, COBRA, and more)
Identify known performance bottlenecks
Deployment platforms
Client target operating system
Server target hardware platform
Server target operating system
Configuration Information
Additional component details
Front-end
Middleware
Tools/Compilers/Libraries
Application architecture details
Workload type (OLTP, OLAP/DSS, both)
Special OLAP/DSS functionality needed
Whether a database access layer is used
Programming languages used to write the application
Database interfaces used by the application (JDBC, OCI, ODBC, stored procedures, and so on)
