Virtualization -- what the heck is it?

[jdelio]

By Sean McLean

@semclean

I'm often asked if I can provide just the bare essentials needed for technical folks to help with a case involving VMware NSX. The response should be brief, high level, cover the bases, the most common problems, and take no more than 5 minutes while somebody is utterly melting down on the phone. I regularly provide this response:

No. No I can't.

I can do this though: I can start blogging about helpful topics in such a way that is informative, easy to read, fun, and doesn't make you want to shoot yourself in the face because it was so dry and boring.

You've heard of "The Cloud". What the living heck is The Cloud, really? Do you remember early attempts at icons to describe networks and The World Wide Web? Back at Apple, I saw oodles of icons that always involved a globe. Meh. (I like the word "oodle" so I frequently measure things in terms of oodles. Don't ask me the difference between Metric oodles and Empirical oodles. I think a Metric oodle is larger than an Empirical oodle by about a cubit.)  We were always drawing network diagrams and for anything that was overcomplicated we drew this nebulous cloud of connections that was iconic for "nebulous stuff where some magic happens."  I swear that's where The Cloud came from. I could be totally making this up, but meh, whatever.

I saw a great t-shirt that summarized 'The Cloud'

There is no cloud. It's just someone else's computer.

There you have it.

So what's the big deal, really? Imagine being able to run a computer on a computer. Let's say you're working on a simple web project and you need a web server and a database server. You have a modern desktop computer, just enough RAM, and oodles of disk space. Your project calls for a web server running on Ubuntu Linux and a database server running on CentOS Linux. Meanwhile you have a shoestring budget and no you can't go buy new hardware.

Enter virtualization

A great solution is to set up two virtual machines that share your desktop computer's resources. You install some virtualization software on your desktop PC, and you download the Ubuntu and CentOS ISOs. You tell your virtualization software (hypervisor) to create two new virtual machines (VMs), each one getting a slice of your hard drive, some RAM, and some basic networking. You tell each VM to boot from one of those Linux ISOs you downloaded earlier and click "start." Holy moly, that first one is booting in a window of its own and your Linux distribution is asking what you'd like to install and how. Just like a regular computer! You configure httpd as needed, get your oodle of package updates, and then you start on the CentOS database server just like you did with the Ubuntu server.

Total cost to you: $0.00

You bought no new hardware. You bought no new RAM, no new hard drives, no monitors, no network cabling, no HVAC, no building permits, no vendors, no purchase requests, no headaches. Nada. You're winning.

Now think about that on a larger scale. What if you could do that with an entire data center? What if you could take all of those servers that are mostly just waiting around consuming space and power and consolidate them onto a much smaller, more manageable server or cluster of servers? That is exactly what's happening all over the landscape of IT today.

There are three flavors that you might consider -- now yes there's a couple of total gear-heads out there shooting up a hand going "ooh ooh ooh you're wrong!" yeah, slow down, I see ya, relax. This is a lightweight blog, not technical canon.

Choose from three flavors

For the sake of argument, consider these three flavors: desktop virtualization like my example here, private cloud, and public cloud.

• Desktop virturalization, we just discussed as our example.
• Private cloud you could think of as those servers in your datacenter all consolidated onto fewer, more centrally managed, beefy servers running in your organization's data center and managed by IT staff. The benefit: it's consolidated, and after some capital expense your costs drop and become mostly operating expense.
• Public cloud you could think of as completely skipping the local data center and running literally on somebody else's computer. You're renting disk space and other compute resources. All of the operating systems, etc. are available from that vendor and customizable by you. This may be managed by your IT staff, or just you (you poor devil). The benefit: This is all operating expenses and your capital expenses were zip. nothing. nada. Oh, that looks killer on a balance sheet! Your boss loves you. Your bottom line loves you. Your investors love you. You are showered with praise and your cubicle is bathed in a glowing light. Sorry, I may have just finished a really good latte from the coffee bar downstairs. It's that good! But seriously, there are some clear benefits to each approach, but I do believe that the Public Cloud approach is a pretty spiffy way to go.

Now imagine what can happen at scale. Imagine being able to save that couple of computers that you defined earlier to a single file. Then saying "ok, make a copy of that for me please" and blammo, now you have a duplicate. Now do it again. You've created a template and you're using it like a cookie cutter. Need to deploy another one on the other side of the globe? No problem; template, cookie cutter, blammo. You're architecting while winning and op-exing and your cubicle is bathed in even gloweringer light (it's a word. honest.).

Private cloud vs public cloud

Yes, there are the fiddly details. For example, the private cloud variety gives you so much control that you're also given all the rope you need to hang yourself. You have an infinite number of things to misconfigure when only one is needed to truly wreck your day. The good news is that vendor's Support Team is filled with Rock Stars who are available to help, all while being only Mostly Wildly Expensive.

The public cloud mostly shields you from that since the lowest level details are handled by the vendor (Amazon, Microsoft, Google... more and more coming). And yes, you still have all the same problems with threats, malware, and the things that people like to try to abuse. That's where our virtual firewall comes into play. We have one that runs on all of the major hypervisors currently and they are really cool. Check out Palo Alto Networks VM-Series firewalls.

This is the power of virtualization.

More soon. And yeah comment, question, whatever. Let's talk. Let's make this a thing.