This content is 16 years old. I don't routinely update old blog posts as they are only intended to represent a view at a particular point in time. Please be warned that the information here may be out of date.
Earlier this month, I managed to attend a Red Hat webcast about their forthcoming virtualisation products. Although Red Hat Enterprise Linux has included the Xen hypervisor used by Citrix for a while now (as do other Linux distros), it seems that Red Hat wants to play in the enterprise virtualisation space with a new platform and management tools, directly competing with Citrix XenServer/Essentials, Microsoft Hyper-V/System Center Virtual Machine Manager and parts of the VMware portfolio.
Red Hat Enterprise Virtualisation (RHEV) is scheduled for release in late 2009 and is currently in private beta. It’s a standalone hypervisor, based on a RHEL kernel with KVM, and is expected to be less than 100MB in size. Bootable from PXE, flash, local disk or SAN it will support up to 96 processing cores and 1TB of RAM, with VMs up to 16 vCPUs and 256GB of RAM. Red Hat is claiming that its high-performance virtual input/output drivers and PCI-pass through direct IO will allow RHEV to offer 98% of the performance of a physical (bare metal) solution. In addition, RHEV includes the dynamic memory page sharing technology that only Microsoft is unable to offer on it’s hypervisor right now; SELinux for isolation; live migration; snapshots; and thin provisioning.
As RHEV approaches launch, it is expected that there will be announcements regarding support for Windows operating systems under Microsoft’s Strategic Virtualisation Validation Program (SVVP), ensuring that customers with a heterogeneous environment (so, almost everyone then) are supported on their platform.
Red Hat seem keep to point out that they are not dropping support for Xen, with support continuing through to at least 2014, on an x86 platform; however the reality is that Xen is being dropped in favour of KVM, which runs inside the kernel and is a full type 1 hypervisor, supporting guests from RHEL3 to 5, and from Windows 2000 to Vista and Server 2008 (presumably soon to include Windows 7 and Server 2008 R2). RHEV is an x64 only solution and makes extensive use of hardware assisted virtualisation, with directed I/O (Intel VT-d/AMD IOMMU) used for secure PCI passthrough together with PCI single root IO virtualisation so that multiple virtual operating systems can achieve native I/O performance for network and block devices.
It all sounds great, but we already have at least three capable hypervisors in the x64 space and they are fast becoming commodity technologies. The real story is with management and Red Hat is also introducing an RHEV Manager product. In many ways it’s no different to other virtualisation management platforms – offering GUI and CLI interfaces for the usual functionality around live migration, high availability, system scheduling, image deployment, power saving and a maintenance mode but one feature I was impressed with (that I don’t remember seeing in System Center Virtual Machine Manager, although I may be mistaken) is a search-driven user interface. Whilst many virtual machine management products have the ability to tag virtual machines for grouping, etc., RHEV Manager can return results based on queries such as, show me all the virtualisation hosts running above 85% utilisation. What it doesn’t have, that SCVMM does (when integrated with SCOM) and that VirtualCenter does (when integrated with Zenoss) is the ability to manage the virtual and physical machine workloads as one, nor can RHEV Manager manage virtual machines running on another virtualisation platform.
The third part of Red Hat’s virtualisation portfolio is RHEV Manager for desktops – a virtual desktop infrastructure offering using the simple protocol for independent computing environments (SPICE) adaptive remote rendering technology to connect to Red Hat’s own connection broker service from within a web browser client using ActiveX or .XPI extensions. In addition to brokering, image management, provisioning, high availability management and event management, RHEV for desktops integrates with LDAP directories (including Microsoft Active Directory) and provides a certificate management console.
Red hat claim that their VDI experience is indistinguishable from a physical desktop including 32-bit colour, high quality streaming video, multi-monitor support (up to 4 monitors), bi-directional audio and video (for VoIP and video conferencing), USB device redirection and WAN optimisation compression. Microsoft’s RDP client can now offer most of these features, but it’s the Citrix ICA client that Red Hat really need to beat.
It does seem that Red Hat has some great new virtualisation products coming out and I’m sure there will be more announcements at next month’s Red Hat Summit in Chicago but now I can see how the VMware guys felt when Microsoft came out with Hyper-V and SCVMM. There is more than a little bit of “me too” here from Red Hat, with, on the face of it, very little true innovation. I’m not writing off RHEV just yet but they really are a little late to market here, with VMware way out in front, Citrix and Microsoft catching up fast, and Red Hat only just getting started.
Consequently, I was pleased to see last night that my netbook had popped a message in Action Center warning me about the scheduled reboot (and prompting me to change the settings).
Over the last month or so, I have gone Twitter crazy. 
