The official announcement has been made: Windows Server 2012 R2 is coming, and it’s bringing a lot of changes to Hyper-V. Yesterday’s announcements from TechEd North America made by Ben Armstrong were amazing – you can check out the recording of his session, already available on Channel 9!
First off, two of the announcements actually update my session from ITCamp 2013 about Running Linux on Microsoft Private and Public Cloud infrastructures – during the session, I did mention that “cool new things are coming”, but I’ve also said that officially, the next iteration of the Linux Integration Services would only contain memory ballooning support, without the memory hot-add. Well, yesterday we got to hear that hot-add will also be there!
I’ll try to cover some of the most important new features coming in Hyper-V 2012 R2 (I’ll start with the Linux ones, as they’re related to my recent session from ITCamp):
- Full Dynamic Memory support for Linux VMs – full hot-add and ballooning support inside Linux VMs
- Online backup for Linux VMs – even though there’s no VSS support in Linux, the Microsoft guys have managed to find a way to create consistent backups of running Linux VMs, by doing what’s essentially called a “filesystem freeze” by briefly stopping all disk I/O inside the VM until the host creates a VSS snapshot of the VM on the host (thus getting a file-consistent backup with zero downtime) – once the snapshot is done, disk I/O is resumed and then the actual file copy process starts
- New video driver for Linux – improved video experience with Linux VMs, similar to the one you would get on Windows VMs
- 2nd generation VMs – now this is huge! Hyper-V in WS 2012 R2 comes with a new generation of virtual machines based on UEFI, with no emulation for unnecessary system components. What you’ll get is a VM using only SCSI controllers (so no more IDE-only OS drives), synthetic network adapters for PXE boot and everything else you need to run fully virtualized OS-es with no device emulation. For this to work, the supported guest OS-es are 64-bit editions of Windows 8, Windows Server 2012, Windows 8.1 and Windows Server 2012 R2
- Live resizing for VHDX files – you’ll now be able to either expand or shrink your VHDX files while the VMs are running; this also works for Linux VMs
- Shared VHDX – Probably the most impactful feature to be included in the new version of Hyper-V: VHDX files can now be shared between two virtual machines using the virtual SCSI controller (if you place them on an SMB share, concurrent access will be handled automatically); this will allow you to easily create guest-level clusters inside the VMs, without the need for iSCSI or Fiber Channel infrastructures
- Guest Automatic Activation – if the Hyper-V host is activated using a Datacenter SKU, all virtual machines installed on it will be activated automatically
- Cross-Version Shared-Nothing Live Migration – you will be able to live migrate VMs from Windows Server 2012 to Windows Server 2012 R2 while the VMs are running, regardless of whether you’re running them in a cluster, if you use shared storage or not, etc.
- Hyper-V Replica improvements – you’ll be able to both set your replication times manually to 30 seconds, 5 minutes (the current default in WS 2012) or 15 minutes, and you’ll also be able to extend the replication (i.e. create a separate replica for an existing replica); for instance, if you’re now replicating a VM from host A to host B, you’ll also be able to create another replica for the VM being replicated on host B to host C
- Live Migration Compression – Live Migration traffic will be compressed in-memory, using any idle CPU power available, reducing the migration speed with up to 50%
- Live Migration over SMB Direct (RDMA) – Live Migration can now benefit from SMB 3.0 and Remote Direct Memory Access (RDMA), allowing for an even faster Live Migration experience
- Live VM Cloning – you’ll be able to “clone” a VM (including the in-memory content) while the VM is running; this will allow you to have a separate copy of the VM (that you could use for debugging purposes, for instance)
- Live VM Export – exporting a VM while it’s running
- Storage QoS – you will now be able to set the minimum and maximum IOPS limit, per VM
- VM Connect enhancements – the console redirect allowing you to connect to the VM from the Hyper-V manager interface used to basically act like a KVM device; with the new Hyper-V version, they’re now using RDP to interact with the VM through the VMBus – this will enable you to use existing RDP features like shared storage, copy/paste for content and files between the VM and the host, audio redirection, etc.
- Compatibility with Windows Azure – right now, Windows Azure is using Hyper-V in Windows Server 2012 as a virtualization platform behind the VM roles, which will give you full compatibility with your on-premise VMs that you’re moving into the cloud, or vice-versa
All in all, some great enhancements all around. Just a reminder, you can go check out Ben’s session from TechEd NA right now!