In some cases, Sun provides hardware support through driver patches. Sun provides these driver patches to support third-party hardware, such as IBM BladeCenter servers. Another reason Sun might provide hardware support is to enable the installation of a particular Solaris release on newer hardware without necessitating the re-engineering of that particular Solaris release. In such instances, it is often necessary to install a particular driver patch. Most often, the process involves installing the latest KU patch for the OS in question.
The miniroot is a minimal, bootable root (/) file system that resides on the Solaris installation media. A miniroot consists of all the Solaris software that is required to boot the system to either install or upgrade the system. The miniroot is what the JumpStart installation program or installation media uses to perform a full installation of the Solaris OS. The miniroot only runs during the installation process.
It is important to understand that the procedure that follows describes how to install a patch on the miniroot image only. When you patch the miniroot image, the patch is not installed on the system where the Solaris OS installation will take place or on the system that the patchadd -C command is run. Patching the x86 miniroot image is strictly used for adding driver and hardware support to the process that performs the actual installation of the Solaris OS. An example of new hardware might be a new motherboard that has driver support in a later KU. The installed image still requires the installation of a patch prior to the first boot. This process occurs after the installation completes. A finish script is invoked, initiating the installation of the KU on the freshly-installed system prior to first boot. This installation of the KU is separate from the x86 miniroot image patch process.