NovaBACKUP Security Blog

What is Virtual Machine Replication?


Let's take a deep dive into one of the facets of virtual machine protection called virtual machine replication (also called virtual replication) and what it can do for a business. The first question that may come to mind is, “what is virtual machine replication?” On a very simple level, virtual machine replication (VM replication) is a type of VM protection that takes a copy of the VM as it is right now and copies it to another VM. Whether that VM is on the same host, different local host, or even a remote host, it all really depends on what you want to do. If you would like more information on why to go virtual in the first place, check out my post Why Should I Look at Virtualization for My Small Business?

Different Types of Virtual Replication

There are several different types of VM replication that give you different restore points, including a near real-time VM replication option that immediately copies the data as it is being written to the VM - giving you a very close to exact copy of the VM in near real-time. There is also a more point-in-time replication option that occurs on a scheduled basis. For example, if you replicate your VM once an hour, you can either have it automatically start when the protected VM fails, or manually start when you want it to be turned on.

In the small business world, I have seen very few instances where a real-time type of VM replication makes sense in terms of the amount of hardware, bandwidth, and cost of software that’s required to do near real-time VM replication. I suggest that small businesses interested in implementing VM replication (in order to have a business continuity/disaster recovery plan), stick with the type of VM replication that does more of a point-in-time snapshot and replication. The number of snapshots that are needed per day really depends upon the business case.


Creating a Business Case for VM Replication

If for example, I know that a crash of the main server for my business will bring down all incoming orders. And, if I know that I average $500 in sales every hour from 8am to 5pm, then an average day’s sales would be $4,500. This means that if I am down for an entire day, that is $4,500 in potential sales I lost. This tells me that I would be willing to spend at least $4,500 (the cost for a single day’s worth of downtime), to mitigate this type of downtime.

One way to lessen your risk is to buy another decent-sized server that can handle the very minimal VMs you need to keep your business going.  For example, if this costs about $3,000 to install with some local storage to run the VMs, that gives you $1,500 for the hypervisor of your choice and software to do the replication. Hyper-V can be free depending on what you are doing, while VMware will cost you around $600 to give you what you need to do this. This leaves less than approximately $900 for the replication software, which means you need a piece of software that backs up and replicates VMs on a schedule to stay on budget.

You may want to look at your environment to determine if you also need to back up any physical machines or specific applications on those VMs differently, like a SQL server. There are very few pieces of software that will give you all of the features we are talking about, and even fewer that will fit into this budget. NovaBACKUP Business Essentials will do all of the above, and do so within this budget. With this solution, you have everything you need to mitigate a day of downtime in the future for the price of less than a single day.

Obviously, these numbers are not going to work for everyone and the hardware price can be reduced in a lot of cases, but it should give you an idea of how you can justify putting together a business continuity plan without blowing a large budget on hardware and software.