VI3 Review Extra: VMware administrator's features
Improved VM snapshotting, useful cloning, and rich performance reports round out the VI3 management toolsFollow @pvenezia
Reporting VirtualCenter 2 and VI3 provide some seriously thorough performance data, which is gathered at the host and VM level. Useful graphs are available at the click of the mouse, and data exports in CSV format are also readily available. All of this data is gathered by the VMware agent running on all VMs and reported back to the VI3 host. The only problem we encountered here was a Red Hat Enterprise Linux 4 VM that had a fully functional VMware tools installation, and then suddenly didn’t. Performance data on that host was no longer available, although host-initiated actions such as guest shutdown worked. The end result was that this VM was orphaned, because Distributed Resource Scheduler had no data with which to make resource management decisions. The problem wasn’t resolved by reinstalling the tools, and it remains a mystery. No other VM exhibited this behavior, but this small perplexing problem had some Fergenschmeir admins grumbling.
Delegated administration But the Fergenschmeir techs were all happy to see the straightforward user and group management within VI3. By attaching to an Active Directory domain, VirtualCenter can take full advantage of the user and group layout of the directory in determining who gets access to what. Based on a cluster, host group, or individual server level, administration of virtual machines can be delegated granularly. For Fergenschmeir, this meant defining one host group for the Web servers and another for internal file/print and Exchange servers. Members of the Active Directory Webmasters group had full access to the Web and MySQL VMs, but couldn't even see the others, while the converse was true for the internal Windows admins.
Network-based licensing New to VI3 is FLEXlm licensing, whereby a license server running on the VirtualCenter server distributes licenses to participating VI3 servers over the network. Unlike many FLEXlm installations, however, VI3 servers do not continuously communicate with the license server, but check out a license during boot, and then refresh that license every week or so during normal operation. The license keys are installed on the VirtualCenter server as a single file.
When a new VI3 host is built, it is unlicensed. Installing these licenses per VI3 host requires configuring the license server IP address on the VI3 host through the configuration pane of VirtualCenter and selecting the options desired on that host.
Extensibility Finally, VMware VI3 and VirtualCenter both come with a thorough API, and every function present in VirtualCenter is available via a SOAP interface. This makes customization not just possible, but simple. The network stack, for instance, is fully modular, allowing custom code to be inserted along the way to permit vendors or more advanced IT shops to introduce their own code into the mix to provide functions not already present in the solution. Also, as mentioned before, it’s relatively simple to script VirtualCenter actions to be triggered on alarms or manually.