Feeds

Virtualisation for Beginners

It's not just for server jockeys, you know

  • alert
  • submit to reddit

Top 5 reasons to deploy VMware with Tegile

Your first ventures into virtualisation will probably be some variation of this, as a prop to run an old app on a new operating system. Running Windows apps on your Mac is an obvious example, and this opens up another useful possibility. The Mac understands Windows filesystems pretty well, but it can't, for example, write to NTFS. A Windows virtual machine running inside Mac OS X would get round this problem.

Virtualisation for Beginners

The cute 'Active Corner' in action. It curls down when approached by the mouse cursor, and a click on the exposed background switches into Window mode.

A practical example of this came up recently when a Nas device in an all-Windows shop failed. Users were able to recover the hard drive, but it was formatted for the Linux Ext 3 filesystem, which Windows can't read. A simple solution was to create a Linux virtual machine running under Windows, and recover the files from there.

Managing Virtual Machines

Virtual machines can grow very large. Typically, on creation, the machine will be allocated some maximum disk space, say 50GB, but will initially occupy only a tiny proportion of that within the host operating system's file space. As new files are added the space occupied grows dynamically, but this space isn't released when files are deleted within the guest - one more reason for ensuring data is stored outside your virtual machine.

Parallels offers a utility, Parallels Compressor, that can be applied to an offline virtual machine to seek out deleted space and remove it, shrinking down the virtual machine. Unfortunately, this valuable facility is close to useless in practice, because the utility refuses to function with virtual machines that have been snapshotted, and snapshotting is pretty well a fundamental requirement.

The problem is that snapshots store more than just the files within the VM - they also store the state of the processor and the entire contents of memory. "And the file system is not in a synchronised state," says Stas Protassov, Senior Vice President of Virtualisation and Storage at Parallels, "and you could corrupt the file system."

An update sometime next year is expected to fix this problem and make snapshots and the compressor compatible. Once this is in place Parallels foresees offering the option to run the compressor permanently in the background.

Beginner's guide to SSL certificates

More from The Register

next story
Bada-Bing! Mozilla flips Firefox to YAHOO! for search
Microsoft system will be the default for browser in US until 2020
Be real, Apple: In-app goodie grab games AREN'T FREE – EU
Cupertino stands down after Euro legal threats
Download alert: Nearly ALL top 100 Android, iOS paid apps hacked
Attack of the Clones? Yeah, but much, much scarier – report
SLURP! Flick your TONGUE around our LOLLIPOP – Google
Android 5 is coming – IF you're lucky enough to have the right gadget
Microsoft: Your Linux Docker containers are now OURS to command
New tool lets admins wrangle Linux apps from Windows
Facebook, working on Facebook at Work, works on Facebook. At Work
You don't want your cat or drunk pics at the office
Soz, web devs: Google snatches its Wallet off the table
Killing off web service in 3 months... but app-happy bonkers are fine
prev story

Whitepapers

Choosing cloud Backup services
Demystify how you can address your data protection needs in your small- to medium-sized business and select the best online backup service to meet your needs.
Getting started with customer-focused identity management
Learn why identity is a fundamental requirement to digital growth, and how without it there is no way to identify and engage customers in a meaningful way.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Internet Security Threat Report 2014
An overview and analysis of the year in global threat activity: identify, analyze, and provide commentary on emerging trends in the dynamic threat landscape.
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.