Virtual Server technologies are one of the big focal points in tech today. Consolidating servers onto single physical machines is the now, it’s here and the buzz on the tech side of business is all about VM’s!
Virtual Computing (in non-tech speak) is the creation of multiple *virtual* operating systems ON TOP OF an existing *host* operating system while making all this happen on one physical computer box. Vitualization brings with it the ability to move, relocate, restore, and reconfigure systems very quickly. It makes moving *old school* technology onto newer boxes easy. It reduces costs and well…. it’s just plain cool.
One of the factors spurring the virtual wave is adoption. Business are beginning to acknowledge the validity and advantages of using VM’s (virtual machines). Virtualization is affordable and technically reasonable to achieve -and- these statements remain true even for small to medium sized business (which means large scale adoption is coming). Bottom line, running more computers on top of one computer has become reality in the every day world. For technology professionals, as we work through the year and then look back at the end, 2008 may be noted as the year of the virtual machine.
So why use them? The benefits of using Virtual Machines include:
- reduced utility costs
- (moving multiple physical machines onto a single server running virtual machines cuts electricity bills)
- simplified management
- (multiple machines can be managed from a single chair using System Center Virtual Machine Manager)
- fast migration from machine to machine
- (virtual hard disks [which are digital snapshots representing an entire computer system] can be moved from place to place very quickly)
- extremely fast system restores compared to traditional environments (think disaster recovery)
- non invasive low cost testing
- (ex. Companies can use virtual servers instead of physical ones to test applications. This is an effective low cost method for testing systems prior to deployment.)
- dynamic data center
- (virtual machines can be reconfigured and redeployed in a live environment very quickly allowing business to adjust dynamically operational and strategic needs)
Each day this week, I’ll review the existing Microsoft technology, Microsoft Virtual Server 2005 R2 (which works on many of today’s servers). We’ll review features, basic walkthroughs and start with installation tips in this article below. Next week, we’ll move onto the virtual machines of the future and take a look at Microsoft Hyper-V in Windows Server 2008 (tech note – Hyper-V requires the Intel VT or equivalent AMD processor).
It is time to tune in to virtual computing technology.
Reading and Watching
- Virtual Server 2005 R2 Product Documentation
- Virtual Server 2005 How To
- Virtual Server 2005 R2 Checklists
- Microsoft Server Virtual Technical Resources
- Virtual Server Webcasts
Let’s take a look at some best practices regarding Virtual Server planning, deployment and daily use. We’ll begin today with best practices and move on in our next article to installation.
Best practices for Virtual Server 2005 R2
To review a more detailed article please read this Best Practices article at Microsoft
Disk Space
- It is essential that you allow the additional hard disk space that will be required by all operating systems you plan to deploy. You will need room for
- host Operating System
- each Guest Operating System
- each Guest Operating Systems paging file
- all dynamically expanding virtual hard disks (data on the Guest)
- the space need to save the contents of each virtual machines RAM when putting the VM into a saved state
Memory
- enable Physical Address Extension (PAE) X86 on the Host operating system. This allows the host to access more than 4 gigabytes of physical memory.
- DO NOT enable PAE X86 on the virtual machines. Virtual machines can only access up to 3.6 GB of memory each (therefore unnecessary on the VM)
Network Adapters
- configure network adapters as needed to accommodate the traffic generated by the virtual machines on each physical server
- recommendation is for two or more network adapters
- one adapter should be dedicated for use by the host operating system
- TO DO THIS – unbind the Virtual Machine Network server from the dedicated network adapter
- additional adapters should be dedicated to virtual machines as needed
- UNBIND all network protocols (ex TCP/IP, IPX/SPX, etc..) except for the Virtual Machine Network service from all other network adapters being used for Virtual Machines
File System
- Use NTFS as the file system
- limit access to the Administration Website
- limit access to the (.vmc) files, virtual hard disk (.vhd) files, and virtual network configuration (.vnc) files
Folder Naming and Locations for Virtual Machines
- DEFAULTS
- by default, all virtual machine configuration (.vmc) files and related files are created in the Shared Virtual Machines folder.
- Virtual Machines consist of two primary components
- Virtual machine general configuration (.vmc)
- Virtual hard disk (.vhd)
- Virtual Machines consist of two primary components
- TO DO’s
- Organize (create) folders as needed to reflect your organizational structure (you can move away from the default Shared Virtual Machines folder)
- Keep individual virtual machine components in a single folder
- name the each VM folder in the name of <VirtualMachineName>
- (all files used by the VM will be stored in this folder)
- name the each VM folder in the name of <VirtualMachineName>
- configure security using NTFS in a manner appropriate to you Domain/environment and to each Virtual Machine
- RUN SysPrep on virtual hard disks (.vhd)
- you MUST run sysprep on each (.vhd) for the (.vhd) to be portable
- run sysprep on the any (.vhd) before you make copies of the (.vhd). This assures that every operating system remains unique if moved to another host system.
- sysprep is on every Windows Server 2003 -OR- Windows XP install disk
- OPEN Support\Tools folder
- OPEN Deploy.cab
- for Help with sysprep see the Microsoft Windows Corporate Deployment Tools Users Guide (Deploy.chm on the OS install disk)
Install Virtual Machine Additions
- Install Virtual Machine Additions in EACH virtual machine installed on the host.
- see this article
Additional Best Practices
- DO NOT use VMRC (Virtual Server Remote Control) over a Terminal Services connection
- it is OK to access the VM directly using Terminal Services (mstsc.exe) BUT DO NOT access the host with RDC and then use the VMRC in the host to connect to the VMs
- SHUT DOWN virtual machines when making changes
- when copying or moving (.vmc OR .vhd), shut down the Virtual Machine
- SHUT DOWN virtual machines prior to power down the Host Server
- avoid corruption etc… of the virtual machines which are not automatically shut down when powering down the Host server
- user Relative weight option (on CPU Allocation page) to allow each Virtual Server to adjust CPU usage dynamically as needed by the VM
Domain Controllers on Virtual Machines
- DO NOT enable host time synchronization on a Virtual Machine that is configured as a domain controller. User an external time source such as time.microsoft.com
For a complete review of Best Practices please read this article – Best Practices for Virtual Server and these Checklists
See you when we jump into Part 2 of 5 “Our first installation”