Xen masters take aim at VMware
Virtual Iron and XenSource offerings lack power and polish of the virtualization leader, but they're gaining fastFollow @pvenezia
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I did run into some significant problems with Virtual Iron. It seems that Virtual Iron's management framework uses the MAC (media access control) address of the management interface on each server as a unique identifier. When I swapped out interfaces on one of the servers, I suddenly had three orphaned VMs and duplicate entries for their physical host. After discussing the problem with Virtual Iron, it became clear that the easiest way to fix the problem was to reinstall the management server. It's possible to manually alter the management server's database to solve this problem, but it's far simpler to reinstall, rediscover the hardware resources, recreate the VMs, and remap the disk volumes. Taking this simpler route, I was able to retrieve all the orphaned VMs, although all disk identifiers were wiped out, leaving me guessing which disk volume belonged to which VM.
During this adventure, the management interface exhibited some very odd behavior, even locking up a few times. All in all, this experience proved to be a mixed bag: It's disconcerting that it happened at all, but it was corrected without the loss of any VMs.
Virtual Iron Enterprise contains enterprise-level features such as VM snapshots, LiveMigrations, and LiveCapacity. LiveMigrations are the Virtual Iron equivalent of VMware's VMotion, where a VM is moved between physical hosts without requiring a reboot. LiveCapacity corresponds to VMware's Distributed Resource Scheduler, allowing the management server to make decisions on VM placement on a server farm to compensate for unbalanced loads. In practice, all of these functions worked nicely: LiveMigrations occurred quickly and without interrupting processes on the VM, and LiveCapacity adequately shuffled VMs around. In addition, there's nascent support for IPMI (Intelligent Platform Management Interface), providing some offline server maintenance capabilities.
On the monitoring end of things, Virtualization Manager has performance graphing and reporting features, gathering individual VM performance metrics though the use of the VS Tools packages installed on the VMs themselves. The graphs are presented in real time, and they can be laid out in a grid and digested at a glance. The reporting tools pop out HTML pages with the requested information. Both the graphs and reports look good, but they need some work to be truly useful, such as greater trend analysis and more output formats.