IT professionals are always looking for better ways to manage virtual machines in the cloud. Today, the search often includes evaluating an immutable infrastructure as the best solution.
Understanding immutable infrastructure
Merriam-Webster defines immutable as "not capable of or susceptible to change." It may seem counterintuitive to apply that term to an IT infrastructure. Most people are familiar with mutable infrastructures.
A mutable infrastructure is tuned and tweaked, as changes are required. IT departments build immutable infrastructures to specific requirements without ever changing it.
If the original specifications need to change, the IT department develops a new infrastructure. The old infrastructure is obsolete and the new one replaces it entirely.
Virtualization is the key technology that makes an immutable infrastructure possible. It wouldn't be cost effective to replace physical hardware every time a change is required. However, the virtualization of hardware and software for networking, servers, and storage creates a new world of opportunity.
Immutable infrastructure has many strategic advantages for medium- to enterprise-level companies.
Reduces support calls
Organizations that use immutable infrastructure receive a significantly lower number of support calls. When issues do arise, they're finding it much easier to resolve those issues by deleting the instance causing the problems. It's also possible for the engineering staff to quickly trace that failure back to a root cause and update the system to eliminate it.
Improves security incident resolution
One of the big challenges when responding to security incidents is the blurred line between a normal operation and an exception. An immutable infrastructure is very clear about the line between those two states.
As a result, exceptions are easier to identify and machine learning can replace manual rules to spotting them. With versioning occurring at the container level, that baseline is a reliable reference for normality. It's possible to prevent some exceptions before they occur.
Takes advantage of whitelisting for security
Security personnel can take advantage of the immutable infrastructure and whitelisting. For example, if a particular application should never consume a specified amount of memory, whitelisting will enforce that rule. The whitelisting will help to thwart security breaches in real time, and the security team will be able to spot the attack.
Applications can be deployed securely using whitelisting. Tests conducted on an image will prove or disprove compliance. The new application can be deployed with security in place.
In the same way, whitelist configuration changes can be tested against the latest version of an application before deployment.
Eliminates configuration drift
Whenever you're not sure that all your servers have the same configuration, supporting the servers becomes a time-consuming task. This usually happens when multiple instances of the server definition are running at once. All it takes is for someone to change a server configuration manually, and it can cause a lot of chaos.
Using an immutable infrastructure, there is only one instance of a server configuration running. And that instance was thoroughly checked before being deployed.
Eliminates synchronization tasks
When instances are updated while they're running, problems with security and configuration drift can pop up. The typical answer to that problem is continuous synchronization.
In continuous synchronization, scripts run regularly to update configuration changes that have been made since the last update. Unfortunately, this process will sometimes temporarily create misconfigured servers. From a security standpoint, the process may overwrite malware, but it's not a sound security strategy.
An immutable infrastructure eliminates the need for synchronization.
Takes advantage of cloud capabilities
The cloud is already built to support immutable infrastructures. The ability to remove and create virtual machines on the fly is already part of the cloud environment. And they perform that function in a way that doesn't disturb applications.
Further, the cloud systems will switch traffic between instances in a way that preserves an instance until all running transactions are completed.
Produces fast recoveries
When the DevOps team deploys a new instance, they also save the old instance. If a rollback is required, restoring the old instance is an easy and quick way to make the rollback happen. In addition, you know that the older version works.
Any tech team would enjoy having an easy and safe way to experiment. With immutable infrastructures, they can experiment safely. The rollback capability takes the fear out of experimentation and supports innovation.
Immutable infrastructures will undoubtedly become more common as more organizations move to the cloud. The advantages of better security and easier management are difficult to ignore.
In addition, you'll be able to save a great deal of time. The resource drain caused by configuration drift and synchronization will be a thing of the past. Better security and fast recovery will become standard.
Your team will be free to experiment more than ever before, allowing them to come up with more innovative solutions to business problems.
In today's cloud environment, a new mindset will allow your organization to move from older, time-consuming ways of managing servers and virtual machines to a contemporary approach that takes advantage of new technology and new thinking.