The platform requirements for deploying multiple Portal Server communities on single Derby instances include the following:
Operating System
Solaris 9 U6 or Solaris 10 on SPARC
Solaris 9 or Solaris 10 on x86
RedHat Enterprise Linux 2.1, 3.0 Update 3 or 4.0 on x86.
For more detailed information please refer to the release notes.
These requirements are similar to those required for setting up any portal instance. The requirements for setting up a dedicated derby instance also require the use of Java SDK which is normally packaged with the Java Enterprise System 5. The required version is 1.5.0_09 or later.