What Is Failover?

Jun 26, 2019

What Is Failover?

BY Tobias Geisler Mesevage

Let's Get Technical

To better ensure that your operations can be sustained if disaster strikes your organization, then you should consider implementing a protective failover procedure. Whether hamstrung by a human error or neutralized by a natural disaster, the best way to safeguard the mission-critical components of your technology stack is to tether them to failover replications. With properly set up and managed failover systems in place, your organization will be able to continue to run without any crippling interruptions due to unexpected failures.

What is Failover?

Failover is the consistent capability to seamlessly and automatically transfer the operations of your organization’s important business technology systems (database, server, network, applications, etc.) to a highly reliable backup. These transfers occur if all, or any part of, your primary systems fail or are temporarily shut down. The failover system can be operated as a total redundancy that runs simultaneously with your primary system. All data that is imputed into and processed by your primary system will also be registered in your failover system.

The purpose of a failover system is to eliminate, or at least greatly mitigate, the impact on end-users when a primary system is subjected to a disruption. The end-user should be none the wiser to the fact that a failure has occurred as their requests will be redirected to the failover system that completely mimics the operations of the primary system.

How Does a Failover Work?

In order to function properly, a failover system relies on a direct connection to communicate with the primary system. This connection is called a “heartbeat.” The heartbeat will usually send a pulse every few minutes from the primary system to the failover system. As long as the pulse stays consistent the failover system will remain dormant.

Once the regular interval of the heartbeat connection is interrupted, the failover system will initiate and assume the operations for all of the primary system’s work. You can usually configure your failover systems to automatically notify your IT team of the failure so they can work on getting the primary system functioning properly again, as soon as possible.

Benefits of Failover Systems

Protection from Downtime

Deploying reliable failover systems for the mission-critical components of your organization’s technology stack should greatly reduce any downtime that would potentially result from service failures. If even one of the components of any of your crucial systems fails, then it will prohibit the proper functionality of every component that interacts with it.

With a failover system jump-starting into service almost immediately once the heartbeat connection is lost, your staff can continue working without any major disruptions. Enabling them to perpetually provide your customers and clientele with exceptional service.

Prevents the Loss of Revenue

If a vital business application, say your payment processing service, is compromised for an extended period of time, then your organization’s profitability will most likely come to grinding halt. The consumer can be a very fickle creature; so even a single subpar experience can permanently dissuade them from ever considering your organization’s products or services again.

Having failover systems set up will provide an extra layer of defense that will better ensure your organization’s efficiency and balance sheets aren’t hampered by technological failures.

Drawbacks of Failover Systems

Comes with a Hefty Price Tag

Setting up, running and managing a robust and protective failover procedure can be an exceedingly costly endeavor. Especially if you wish to ensure that each and every component of a highly complex and highly connected landscape has their own dedicated failover system.

In order to deploy reliable failover systems that will run atomically with minimal downtime, you're going to have to spend a lot of cash on high-bandwidth systems that are equipped to conduct synchronous data transmissions. These seemingly considerable costs are not wholly derived from hardware and software purchases. A substantial portion of the total line item costs for the failover systems can be due to potentially having to rely on third-party expertise to install and manage the systems.

However, utilizing virtual machines to host your failover systems can significantly reduce the costs of deploying a failover solution compared to relying on physical hardware.

Lengthens the System Maintenance and Quality Assurance Processes

To properly function and protect your organization’s technology, failover systems require the same maintenance and quality assurance verification as your primary systems. A greater amount of labor will need to be squeezed into already tight maintenance windows, as running your primary and failover systems on different versions mainly defeats the purpose of having identical and synchronized systems in the first place.

You will also need to regularly verify that your failover systems can communicate and interact with the various components that comprise your landscape. Executing these verifications can nearly double the time that your IT staff allocates for testing and quality assurance.

Benefits of Failover Systems Greatly Outweigh their Drawbacks

In conclusion, deploying protective failover procedures for your organization’s critical technology infrastructure is a highly encouraged practice to ensure business continuity. Preventing the potential lost revenue from a lengthy system disruption is well worth the capital expenditure of purchasing and managing failover systems. The additional time required by your IT staff to maintain and test the failover systems could potentially be a pittance compared to the stressful hours, or even days, it could take to incorporate a replacement component into a landscape if the failed component is unsalvageable.

Failover systems can greatly enhance your organization’s operational fitness and agility. Find out more about Datto to learn more about failover systems and disaster recovery strategies.