IBM is offering an annual support option for the free version of its DB2 database, the first of the top three database vendors to make such a move.

Customers using IBM's DB2 Express-C database can now buy a one-year subscription for the software, including support, for USD 2,995 before tax, according to information on IBM's Web site.

Customers who buy a subscription for two servers can build a high-availability configuration using clustering or the High Availability Disaster Recovery feature, without having to buy additional software, IBM said. The subscription also includes around-the-clock technical support, maintenance and upgrades.

IBM, Oracle and Microsoft each offer a free version of their databases, which have been seen as a way to ward off competition from open-source rivals. They each come with usage restrictions, however. IBM's is designed for use on servers with up to 4G bytes of main memory and one or two dual-core x86 processors, or two cores of any other type of processor. IBM does not limit the amount of data that can be stored in the database.