Posted by: AlyssaWood
KVM, P2V, Red Hat, Xen
BOSTON — By nature, virtual machines (VMs) are movers and shakers. The tools in Red Hat Enterprise Linux (RHEL) 6 perform the essential tasks of virtual-to-virtual (V2V) conversions, physical-to-virtual (P2V) conversions and live migrations, but they still have room for improvement.
Matthew Booth, a Red Hat senior software engineer, revealed a few expected improvements at the Red Hat Summit this week. RHEL’s P2V conversion tool, virt-p2v, is still fairly new, so the company is working on faster conversion times and improved fixed-storage transfer options, Booth said.
If your organization is just starting to virtualize, P2V conversion is a critical first step. Slow conversions can complicate virtualization implementations, so RHEL 6 needs to step up its game in this area.
When it comes to V2V conversions, Red Hat is better prepared. RHEL 6 supports the Kernel-based Virtual Machine (KVM) instead of the previous versions’ Xen hypervisor, so many admins are now tasked with converting VMs from Xen to KVM.
Summit keynotes stressed the idea that open source offers choice — something that’s reflected in RHEL’s virt-v2v conversion tool. It supports conversion from Xen to KVM, RHEL 5/6 KVM to Red Hat Enterprise Virtualization (RHEV) VMs, and even VMware ESX to RHEL 5/6 KVM or RHEV.
RHEL 6.1 will also offer new V2V features. For one, the virt-v2v tool will be able to convert a VM’s storage format and convert from pre-allocated to sparse storage.
RHEL 6 live migration
Migrating VMs from one host to another in RHEL 6 or RHEV is similar to VMware vMotion or Hyper-V Live Migration. But vMotion offers something that RHEL 6 live migration does not — the ability to migrate VMs from one data center to another, using Cisco Systems’ Overlay Transport Virtualization.
Live migration between geographical locations is invaluable for disaster recovery (DR). After a failure, you can simply migrate your VMs to a remote DR site. But, Jesse Stanley, a virtualization solutions architect at Red Hat, said even live migration across different regions in the United States isn’t recommended with RHEV, particularly because its success depends on Ethernet speed and other external factors.
Still, live migrations within the same infrastructure are pretty impressive. I was able to watch Stanley live-migrate a desktop to a laptop with a single right-click — all while the desktop played a YouTube video with no interruption. The live migration took only a couple minutes.
In RHEL 6, Red Hat also improved the performance and speed of live migrations with large memory VMs.