Continuing my week in Chicago, I decided to attend some of the presentations from the System x side. This is the advantage of running both conferences in the same hotel, attendees can choose how many of each they want to participate in.
Wayne Wigley, IBM Advanced Technical Support (ATS), presented a series of presentations on different server virtualization offerings available for System x and BladeCenter servers. I am very familiar with virtualization implemented on System z mainframes, as well as IBM's POWER systems, and have working knowledge of Linux KVM and Xen, so I was well prepared to handle hearing the latest about Microsoft's Hyper-V and VMware's Vsphere version 4.
- Microsoft Hyper-V 2008
Hyper-V can run as part of Windows 2008, are standalone on its own.Different levels of Windows 2008 include licenses for different number of Windows virtual machines (VMs).Windows Server 2008 Standard includes 1 Windows VM, Enterprise includes 4 Windows VMs, and the Datacenter edition includes unlimited number of Windows VMs. If you want to run more Window VMs than come included, you need to pay extra for each additional one. For example, to run 10 Windows VMs on a 2-socket server would cost about $9000 US dollars on Standard but only $6000 US dollars on Datacenter edition (list prices from Microsoft Web site).
Unlike VMware, which takes a monolithic approach as hypervisor, Hyper-V is more like Xen with a microkernelized approach. This means you need a "parent" guest OS image, and the rest of the Guest OS images are then considered "child" images.These child images can be various levels of Windows, from Windows XP Pro to Windows Server 2008, Xen-enabled Linux, or even a non-hypervisor-aware OS.The "parent" guest OS image provides networking and storage I/O services to these "child" images.For the hypervisor-aware versions of Windows and Linux, Hyper-V allows optimized access to the hypervisor, "synthetic devices", and hypercalls. Synthetic devices present themselves as network devices, but only serve to pass data along the VMBus to other networking resources. This process does not require software emulation, and therefore offers higher performance for virtual machines and lower host system overhead.For non-hypervisor-aware OS images, Hyper-V provides device emulation through the "parent" image, which is slower.
Microsoft System Center Virtual Machine Manager (SCVMM) can manage both Hyper-V and VMware VI3 images.Wayne showed various screen shots of the GUI available to manage Hyper-V images.In standalone mode, you lose the nice GUI and management console.
Hyper-V supports external, internal and private virtual LANs (VLAN). External means that VMs can communicate with the outside world over standard ethernet connections. Internal means that VMs can communicate with "parent" and "child" guest images on the same server only. Private means that only "child" guests can communicate with other "child" images.
Hyper-V supports disk attached via IDE, SATA, SCSI, SAS, FC, iSCSI, NFS and CIFS. One mode is "Virtual Hard Disk" (VHD) similar to VMware VMDK files. The other is "pass through" mode, which are actual disk LUNs accessed natively. VHDs can be dynamic (thin provisioned), fixed (fully allocated), or differencing. The concept of differencing is interesting, as you start with a base read-only VHD volume image, and have a separate "delta" file that contains changes from the base image.
Some of the key features of Hyper-V 2008 are:
- Being able to run concurrently 32-bit and 64-bit versions of Linux and Windows guest images
- Support for 64 GB of memory and 4-way symmetric multiprocessing (SMP) per VM
- Clustering for High Availability and Quick Migration of VM images
- Live backup with integration with Microsoft's Volume Shadow Copy Services (VSS)
- Virtual LAN (VLAN) support, and Virtual and Pass-through physical disk support
- A clever VMbus, virtual service parent/client approach to sharing hardware
- Optimized performance options for hypervisor-aware versions of Windows and Linux, and emulated supportfor non-hypervisor-aware OS images.
- VMware Vsphere v4.0
This was titled as an "Overview" session, but really was an "Update" session on the newest features of this release. The big change appears to be that VMware added "v" in front of everything.
- Under vCompute, there are some new features on VMware's Distributed Resource Scheduler (DRS) which includes recommended VM migrations. Dynamic Power Management (DPM) will move VMs during periods of low usageto consolidate onto fewer physical servers so as to reduce energy consumption.
- Under vStorage, vSphere introduces an enhanced Plugable Storage Architecture (PSA), with supportfor Storage Array Type Plugins (SATP) and Path Selection Plugins (PSP). This vStorage API allows forthird party plugins for improved fault-tolerance and complex I/O load balancing algorithms. This releasealso has improved support for iSCSI, including Challenge-Handshake Authentication Protocol (CHAP) support.Similar to Hyper-V's dynamic VHD, VMware supports "thin provisioning" for their virtual disk VMDK files.A feature of "Storage Vmotion" allows conversion between "thick" and "thin" provisioning formats.
The vStorage API for Data Protection provide all the features of VMware Consolidated Backup (VCB). The APIprovides full, incremental and differential file-level backups for Windows and Linux guests, including supportfor snapshots and Volume Shadow Copy Services (VSS) quiescing.
VMware introduces direct I/O pass-through for both NIC and HBA devices. While thisallows direct access to SAN-attached LUNs similar to Hyper-V, you lose a lot of features like Vmotion, High Availability and Fault Tolerance. Wayne felt that these restrictions are temporary, that hopefully VMwarewill resolve this over the next 12 months.
- Under vNetwork, VMware has virtual LAN switches called vSwitches. This includes support for IPv6and VLAN offloading.
The vSphere server can now run with up to 1TB of RAM and 64 logical CPUs to support up to 320 VM guest images.Each VM can have up to 255GB RAM and up to 8-way SMP.Vsphere ESX 4 introduces a new virtual hardware platform called VM Hardware v7. While Vsphere 4.0 can run VMs from ESX 2 and ESX 3, the problem is if you have new VMs based on this newer VM Hardware v7, you cannot run them on older ESX versions.
Vsphere comes in four sizes: Standard, Advanced, Enterprise, and Enterprise Plus, ranging in list price from $795 US dollars to $3495 US dollars.
While IBM is the #1 reseller of VMware, we also are proud to support Hyper-V, Xen, KVM and other similar products.Analysts expect most companies will have two or more server virtualization solutions in their data center, and it is good to see that IBM supports them all.