Many software packages have the ability to be upgraded rather than re-installed. Most of the time, admins opt for the latter. The reason is that upgrades can bring about problems that aren't seen with bare-metal re-installations. Anyone who upgraded to Windows XP from Windows 2000 knows that this is true—but in the case of ESX 3.5, the upgrade procedure seems to be very thorough. Several weeks since, it has not caused any problems at all.

Fun with Virtual Servers

VMware admins will notice a few new things right off the bat with VirtualCenter 2.5. First on that list are the annoying splash screens that now adorn most of the elements in the VMware Infrastructure Client. They're designed to be large, friendly displays with links to the most common tasks, but for anyone who's used VI3, they're not useful. Thankfully, it's possible to turn these off. Beyond that annoyance, the new VirtualCenter is almost identical to the previous iteration in form and function, with some new buttons linking to the new features. There is one significant departure from the previous version that's worth noting: a new plug-in architecture. By implementing this, VMware has broadened the scope of what VirtualCenter can accomplish, and potentially opened the door to integrating third-party tools into the overall management infrastructure.

The big Consolidation button at the top of the new VC client is an obvious starting point. VMware has integrated its Capacity Planner code into VC2.5, allowing admins to gauge the impact of virtualizing existing physical servers without leaving the console. Coupled with VMware's physical-to-virtual (P2V) conversion tools, this is a built-in method of doing either piecemeal or wholesale migrations of an existing datacenter. Although plenty of third-party tools do P2V and migration planning, having these tools built into VC2.5 is handy for many smaller infrastructures. This feature, which requires administrator-level credentials for Windows systems, will discover servers on specified subnets and monitor their utilization and performance over time. Following this period, reports can be produced that will provide guidance in selecting physical servers ripe for virtualization, and provide a better picture of the overall utilization of an existing infrastructure.

Although too much data can be a bad thing, it's generally not a bad idea to get as many viewpoints on actual server performance as possible when making these decisions. These new consolidation tools will be welcome in many IT departments.

Update Manager, descended from Shavlik's HFNetChkPro, is another big addition to VC2.5. Update Manager not only provides a control panel for applying updates and patches to groups of VMs, either ad hoc or on a scheduled basis, but can automate the entire process, taking a snapshot of the VM prior to patch application and retaining those snapshots for a configurable time period. So even if the patch makes a mess of your server infrastructure, you can quickly roll back to the snapshots and get things back up and running.