Virtual Machines: A Closer Look at Pros and Cons
Virtual machines, or VMs, have become increasingly integral parts of business-oriented computing but they come with both pros and cons leaders should consider. A virtual machine is actually software that acts as an emulator of a computer, executing programs like one. A VM can give a company adaptability in that any networking configurations or installed applications will be set up separately from the host computer.
First, a little background…
What is a VM?
A virtual machine (VM) is software that creates a “guest” server, with its own operating system and applications, that functions separately from its “host” (typically a physical server). In addition, multiple VMs can be hosted on that same device. A hypervisor then provisions and manages the host’s resources, like storage and memory, between the host and its guests.
VMs continue to attract interest from businesses of all sizes due to their beneficial potential impacts on security, cost, scalability, development and more.
That said, no technology comes without possible downsides to consider. Thus, we have created the following breakdown of high-level pros and cons which those new to VMs should keep in mind:
- Can create multiple operating system environments on the same server|
- Virtual machines can provide an instruction set architecture, or ISA, which is different than the hardware host. The ISA serves as the interface between software and hardware.
- When you create your virtual machine, you create a virtual hard disk. Thus, everything on that machine can crash but if it does, it won’t affect the host machine.
- There are security benefits to running virtual machines. For example, if you need to run an application of questionable security, you can run it in a guest operating system. If the application causes damage, it will affect only the guest VM and the issue will vanish once that VM is shut down. Virtual machines also allow for better security forensics by monitoring guest operating systems for deficiencies and allowing the user to quarantine it for analysis.
- Virtual machines are less efficient than real machines because they access hardware indirectly. Running VM software on top of the host operating system means that it will have to request access to storage and memory from the physical device. This process can impact speed so it is vital to work with IT experts who know how to balance resources between physical and virtual systems.
- Because a virtual machine can be spun up in minutes, server sprawl is something administrators need to mitigate through proper processes. Because a new VM allows a developer a fresh start, we have seen instances of 20 or 30 VMs living on a network where only 3 or 4 were necessary. These semi-defunct VMs drain host resources so each organization should have a clear set of rules for provisioning new VMs and for shutting down old ones.
- While a properly-structured VM can’t infect a host, a weak host system can impact its VMs. This usually happens when there are bugs in the operating system. If two or more virtual machines are connected with each other, the infections could spread to others as well.
Is your company considering making use of VMs for the first time? Circulate the above list of pros and cons with your colleagues. Also, contact us and request our one-page summary by email.
All in all, we are huge fans of VMs for some companies due to the flexibility and security they can provide. Also, while there is an up-front cost to consider, VMs can have a beneficial cost impact if used properly over the long term due to lowering the cost of investment needed in physical devices.
Cynexlink has experience with multiple types of hypervisors on both Windows and Mac operating systems. If your organization is considering whether a VM deployment might be right for your network environment, give us a call — we can certainly help guide you to the right decision.