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Virtual Machine Management at Your Fingertips
VMware VirtualCenter 1.1 lets administrators control hundreds of virtual machines from one console.
by Danielle Ruest and Nelson Ruest

November 17, 2004

Quick Facts
VMware VirtualCenter 1.1; VMware GSX Server 3.1
VMware
Web: http://www.vmware.com/products/vmanage/vc_features.html; http://www.vmware.com/products/server/gsx_features.html
Phone: 877-486-9273 or 650-475-5000
Pricing: GSX Server is $1,400 for 2 CPUs and $2,800 for unlimited CPUs. VirtualCenter is $5,000 per license.
Quick Facts: VMware VirtualCenter manages virtual machines running almost any operating system from a central location. Works with both ESX and GSX Server Editions of VMware.
Pros: Simple interface. Works with Microsoft Access, SQL Server, and Oracle. Supports VMware ESX and GSX Server versions. Supports the migration of running virtual machines with no service interruption.
Cons: Database setup other than MS Access is complex. Does not support VMware Workstation as a management target. Configuration is not entirely intuitive.

System administrators working with virtual machines know what godsends they can be in IT departments. The reasons are many, but the most important is the flexibility hosting an operating system inside a file on a laptop, desktop, or server gives you. If you take your virtual infrastructure seriously and your virtual infrastructure is based on either VMware GSX or ESX Server, then you need VirtualCenter 1.1. VirtualCenter (VC) is a single-point management interface for virtual machine management. It lets you group physical hosts into server farms that you can manage and provision from the VC console (see Figure 1). VC presents performance statistics and allows you to balance the load on your physical hosts.

One of the big issues when working with virtual machines (VM) is provisioning. Here, we use VMware (both Workstation and GSX) to run multiple machines in a lab environment. We conduct most of our reviews and evaluations in virtual environments to make sure each product is operating in a pristine OS. Because we have a limited number of physical machines, we run up to four machines on a workstation and four on a server.

Each time we conduct a test, we look at our seed machines. A seed machine can be a Windows Server 2003 member server, a domain controller (DC), a parent and child in a forest, a workstation running XP, a machine that is Windows Server 2003 running as a DC with SQL Server installed, or even just a base machine with SysPrep so that when it boots it becomes a new member server or workstation. Once we select a seed machine, we copy it, rename it, re-insert it into either Workstation or GSX, re-create the shortcut, change the description, and so on. Some new machines live a few hours. Others become more permanent, such as when we're conducting a long-term test. When this occurs, we like to organize the machines by theme, such as a Microsoft Office SharePoint Portal Server 2003 test, an Active Directory (AD) forest with member servers, and so on.

We need reminders. For example, we set up a forest, and the domain controllers in the forest need to be awakened once a month to replicate with each other otherwise they won't work together once the 60-day tombstone limit is reached. We also need a simple way to provision new machines. This way you can create a seed machine that would be a core Windows Server, for example. To create a SharePoint machine, you create a new machine from the core one; to create a Content Management Server machine, you create a copy of the new machine; and so on. We've always wondered if VMware could let us provision all the machines in a lab through one interface. In the past, we've completed all the tasks mentioned above through the file system, and that's not very efficient.

VMware seems to have read our minds when creating VC. It provides a single interface to manage all virtual systems. Version 1.1 was just modified to work with the GSX version of VMware. Formerly, it worked only with the ESX edition. But it doesn't work with the Workstation edition, which in our case is unfortunate. Perhaps a future version will fully support our testing scenario. But don't get us wrong. Although it doesn't fully support our little lab, we can't imagine any data center working with VMware in a production environment not using this tool.

Installation is fairly simple, especially if you decide to use the Microsoft Access database. It's a bit more complex to use an Oracle or SQL Server database because you have to use a semimanual procedure to create the proper database views. Once installed, though, it becomes fairly simple to use. Simply create a farm, add a physical host or more, and proceed. Physical hosts must be added even if you install VC on the server running GSX Server, but once added, VC will automatically detect all existing VMs on that host so they at least don't need to be added by hand (see Figure 2). You can also install a client component to manage all machines remotely.

Once the machines are set up and accessible through VC, you gain the same capabilities the management interface of GSX Server gives you and more (see Figure 3). You can start and stop machines at will, install VMware tools, create alerts, and set permissions on the machine. One of the greatest features of VC is the ability to provision new machines from scratch or through the creation of templates. Templates can also be created from scratch or can be created from existing machines. One caveat, though: Templates can only be created from machines that use SCSI virtual disks. By default, installing Windows VMs creates IDE disks so you'll have to download and use the virtual SCSI driver from VMware, especially if you want to create templates for Windows XP machines. One cool feature of the templates is that when you use them to create a new machine, VC will automatically ask you to name the machine, give it a new IP address, and generate a new security identifier (SID) for it. This means you don't even need to use the SysPrep tool on the template image.

You can also use VC to create alerts letting you know when your VMs are in danger of failing and giving you active resource management. In addition, you can set permissions on machines to ensure no one who does not have access can control any of the virtual hardware you're running. What we really like is the ability to manage and monitor the machines, providing clear descriptions for each machine and allowing you to manage storage locations for each. VC needs to run with its own credentials in your environment to ensure that VMs keep running when you log off your management workstation. You'll have to prepare this account and give it appropriate credentials to maintain the machine environment. Make sure you set a powerful password for this account, as it requires interactive logon rights on your physical hosts.

VMware states that when you add its VMotion tool to VC, you can move VMs from one physical host to another without any service interruption. The claim sounds impressive and interesting to try, but we did not have access to VMotion.

Overall, VC is one of VMware's major differentiators in the VM marketplace. It is a simple, one-stop shop for VM management and should be in every data center that is using a VM strategy based on VMware. It is powerful and lets you manage VMs as they were meant to be, commodities. Imagine running multiple instances of GSX Server on a Microsoft Windows Server 2003, Datacenter Edition with 32 CPUs and massive amounts of RAM. That would provide an amazing datacenter configuration.

About the Authors
Danielle Ruest and Nelson Ruest (MCSE, MCT) are multiple book authors focusing on systems design, administration, and management. They run a consulting company that concentrates on IT infrastructure architecture and change and configuration management. You can reach them at wssmag@reso-net.com.