By Jeff Scheel
As you likely have heard, Arvind Krishna, IBM General Manager for Development and Manufacturing in the IBM Systems & Technology Group, announced that Power Systems would be supporting KVM. This is an exciting announcement for numerous reasons that I'll defer for another posting. For this blog entry, I thought I'd do some question/answer session based on common questions I've been asked in the past couple weeks. However, before I do so, I need to remind you that these are our current thoughts at this time: things may change.
Q: When will KVM be available on Power?
A: The outlook for general availability is next year. However, IBM has already started releasing patches to various KVM communities to support the POWER platform.
Q: On what systems does IBM intend to support KVM?
A: IBM intends to initially support KVM on a limited set of models, targeted at the entry end of the system servers. This strategy supports IBM's efforts to capture the largest growing market, x86 Linux servers in the 2-socket and smaller space.
Q: How does IBM plan to position KVM against PowerVM?
A: IBM remains committed to the PowerVM being the premier enterprise virtualization software in the industry. With KVM on Power, IBM will be targeting x86 customers on entry servers but will offer both KVM and PowerVM to meet the varying virtualization needs PowerLinux customers. However, KVM virtualization technology represents an opportunity to simplify customer's virtualization infrastructure with a single hypervisor and management software across multiple platforms.
Q: What Linux versions from Red Hat and SUSE will provide KVM hosts support on Power?
A: The decision to provide KVM on PowerLinux will be made by Red Hat and SUSE. IBM will be working with them in the months to come and would welcome their support.
Q: What management and cloud software will support KVM on Power?
A: For KVM node management, IBM intends to work with multiple vendors, including Red Hat and SUSE to certify KVM on Power into their system management software offerings. Additionally, IBM plans to contribute any patches necessary to OpenStack to extend the KVM driver to Power. Using this foundation, additional IBM and third-party software should provide a diverse set of management software.
Q: What will software providers need to do to support KVM on Power?
A: Most software provides have become comfortable with some form of virtualization such as PowerVM, VMWare, and KVM. Just like with applications on Linux, software providers should find that applications in the KVM environment behave similarly on x86 and Power platforms. As such, each vendor should understand any challenge KVM on Power would provide.
Q: What operating systems will be supported as guests in KVM on Power?
A: Given that KVM is initially targetted to be released on Linux-only servers, only Linux is planned at this time. IBM plans to certify the latest updates of RHEL 6 and SLES 11 as KVM guests.
Q: How will KVM run on the Power Systems?
A: The design goal of KVM on Power is to be just another hardware platform supporting KVM. As such, the KVM on Power will be true to the KVM design point of a KVM host image that supports one or more guests. PowerVM constructs such as the HMC, IVM, and VIOS will not exist in KVM. Management and virtualization will occur through the KVM host image.
Q: Will KVM run in a PowerVM logical partition (LPAR)?
A: While KVM supports a user-mode virtualization that can run on any Linux operating system, KVM on Power is being developed to run natively on the system, not nested in PowerVM. This is done to enable KVM to run optimally using the POWER processor Hypervisor Mode. As such, the system will make a decision very early in the boot process to run KVM or PowerVM. This is envisioned as a selectable option managed by the Service Processor (FSP)?
Q: Will it be possible to migrate from KVM on Power to PowerVM or vice versa?
A: While the virtualization mode will be selectable on systems, the process of migrating from KVM and PowerVM will require additional steps such that frequent migrations will be unlikely. However, in the case where a customer wishes to upgrade to PowerVM to acquire advanced virtualization capabilities, this migration should be supported. Steps to backup and restore the VM image will be required when migrating in either direction.
Q: Will AIX or IBM I run in KVM on Power?
A: Given that KVM initially runs on Linux-only platforms, support for non-Linux operatings systems has not been planned at this time.
Q: Will Windows run in KVM on Power?
A: Windows does not run on Power Systems. As such, supporting it in a KVM guest VM will not work.
Hopefully, these questions were helpful to folks. As usual, follow-up questions/comments appreciated.