Virtualizing my world

Virtualization is definitely a big trend in computing and I’m growing to love it.

On the Web.

My production server environment is virtualized by the Xen hypervisor; providing a more flexible and cost effective solution.

I like the freedom of complete root access but, given my relatively low traffic volumes, the cost of a dedicated server would be prohibitive. However, Xen provides me with my own little chunk of hardware resources that no other user’s going to break for me.

The great thing is that these resources can be altered very quickly to respond to changes in my requirements; great scalability in a changeable world.

On the Desktop.

I’m also making extensive use of virtualization on my desktop using VMWare Fusion. I’m a Mac user, but one of the attractions of the VMWare product is the interchangeability of any virtual machine (VM) between platforms.

VMWare Fusion.

VMWare have been in the business of Virtualization of a while now, and have a powerful range of products. Whilst many of these are targeted at the enterprise environment, Fusion is definitely a consumer product; in a good way; and the benefits to me so far…

• Surprisingly seamless Windows XP including Office, in my experience a much better product than the sadly neglected Mac version. Fusion has a ‘Unity’ mode, which places these applications, running in a Windows environment, right on my Mac desktop.
• I’ve tried different Linux flavours for the desktop and server, and I haven’t needed multiple machines. A great asset when you like to dabble but don’t have much free space; small house you see; and want to keep the bills down.
• I’ve tried a whole range of software products without the usual worry of messing up my regular working platform, if it all goes wrong I just delete the VM and start again. If I might want to return to this set‒up again, I can take a snapshot of the current installation, or copy the VM file to a backup location so I don’t have to start from scratch each time.
• Finally, I’ve build VMs of the production server for deployment testing. I know that they’re not identical, but they’ve been good enough to iron out problems in build and deployment scripts before unleashing them on the production server itself.

A virtual network.

Fusion has a built‒in DHCP server to provide IP addresses, or they can be assigned by an external network using the bridged network option.

After exploring these options I discovered that I could build a virtual development network right on my laptop and make it as private as I want. Oh, yes, you can fix the IPs the server hands out, making it much easier to edit that hosts file.

The NAT option can access the outside world, to install updates for example, by sharing the host connection. However it’s protected from external access. My physical home network uses NAT via an ADSL router, but this is a great option if you’re likely to take your laptop network out on the road and I use it for the majority of my installations.

If you’re even more worried about unauthorised access to your latest development project, you can use the host‒only option; access only from the host machine or other local VMs using this network set‒up.

With all the VMs using the same network option, they can all see and access one another. So now I can write my code on the host Mac, test deployment to a virtual CentOS Linux server, and check how it looks on Windows. It’s self contained, I can flip between machines and it’s all totally mobile.