The Red Hat Hardware Test Suite (HTS) is a new hardware certification test suite that replaces the Red Hat Ready 2 (RHR2) test suite. HTS has a new command line interface and uses HAL device data via dbus to detect hardware devices and plan testing. The suite of tests is similar to RHR2, with the addition of tests for new RHEL5 virtualization features.

Virtualization is a new feature in RHEL 5, and it is fully supported on PAE enabled i386 and x86_64 architectures. Red Hat requires IHVs to run certification tests using RHEL 5 base server distribution by installing virtualized kernel as a host OS, plus a subset of tests (info, core, memory and storage) using a RHEL 5 fully-virtualized guest.

If the hardware supports virtualization (Intel VT and AMD), certification is applicable only to the tested configuration (VT feature is enabled or disabled), and the hardware must be retested if this setting changes. Red Hat requires IHVs to run certification test using non-virtualized kernel on ppc, s390, ia64 and non-PAE i386 architectures. RHEL 5 base server certification is extended to all other RHEL 5 flavors of OS distributions supported on the tested architecture.