RHEL 6.4 has Hyper-V drivers and Windows 2012 certification
Version 6.4 of Red Hat Enterprise Linux (RHEL), which has just been released, now includes RHEL6 drivers and userland software that makes the Linux distribution run faster and better as a guest on Microsoft's Hyper-V virtualisation solutions. Updated drivers will also help this fourth version of RHEL6 work better on VMware's ESX.
Red Hat has also improved KVM, RHEL's integrated virtualisation option; the hypervisor now supports some of the features of Intel's next generation of processors, such as Advanced Vector Extensions 2 (AVX2), Hardware Lock Elision (HLE) and Restricted Transactional Memory (RTM). The virtio-scsi driver, which allows an RHEL instance running as a guest to, among other things, exclusively use individual SCSI devices, is now fully supported. The driver, which has been in Linux since version 3.4, was already integrated in RHEL 6.3, but just as a Technology Preview feature. RHEL 6.4 is also one of only a handful of products that have been certified by Microsoft's Server Virtualization Validation Program (SVVP) to act as a host for Windows Server 2012.
In addition, Red Hat says it has improved the performance of the parallel Network File System (pNFS), which is no longer a Technology Preview feature and is now covered by the support contract. Improvements to the System Security Services Daemon (SSSD) have had a positive impact on interoperability with a Microsoft Active Directory. A few dozen upgraded drivers as well as some new ones have allowed Red Hat to improve hardware support in the new minor release; the bnx2x driver, for example, has been updated to support Broadcom's 57800, 57810, 57811 and 57840 network chips. The RHEL kernel now includes everything that is needed for Open vSwitch, but the user space tools are still missing and will most likely be part of products based on RHEL 6.4.
The Release Notes and Technical Notes include more details on these and many other changes. Red Hat took six months to develop this minor release, two months longer than usual. The first Linux distributions based mostly or completely on RHEL 6.3 source code should be available free of charge within one to three weeks – at least, that's generally how long the CentOS project and Oracle have needed in the past to release their clones.