What is a single point of failure?
Last updated on January 19, 2023
A single point of failure (SPOF) is any software, hardware, or other flaw that can bring down a system when something catasts articlerophic happens. To prevent downtime and achieve high availability and reliability,mission-critical systems should not have a SPOF. This article discusses the best practices to detect and avoid single points of failure and presents some common examples of SPOFs. For a Virtual Desktop Infrastructure (VDI) solution with failover and load balancing capabilities, download Parallels® RAS.
How to identify a single point of failure
To formulate a mitigation strategy that will address SPOFs, you need to identify these weak points first. This is crucial to prevent potential SPOFs from adversely affecting your operations sometime in the future.
To catch an SPOF early on, consider all factors carefully during system design. The business impact analysis and risk assessment stages are the best times for identifying potential SPOFs.
The hardware comprising your IT infrastructure is a good starting point in this process. If you find any hardware without any accompanying redundancy, identify what will happen to your network when something happens to it and adopt the proper measure to mitigate the impact.
Once you are done identifying potential issues with your hardware, repeat the process for your services and people. Do not hesitate to source help from experts during the identification process, particularly if you do not have enough experienced people.
Past the design stage, prepare a list of all systems and system components used in your organization, including storage devices, servers, internet service providers (ISPs), and networks.
Since SPOF identification is often challenging, you should encourage project team members to participate fully in the process. As it is probable that some people may hesitate to disclose potential points of failure in the system if they get sanctioned, clearly communicate to the team that the end goal of the process is to have a stable and reliable system once it goes into production, not to punish people.
Examples of a single point of failure
Among the many examples of SPOF in the real world are:
- A single piece of server hardware running a mission-critical system. This leads to costly downtime in case of a hardware crash.
- Servers connected to a single network switch. If the switch fails or gets disconnected from the power source, all the servers become inaccessible.
- A single ISP for your internet access needs. When the ISP experiences an outage, and you rely on constant internet access to keep your operations running, this could lead to losses in time and money.
- A single employee, subject matter expert (SME), or consultant assigned to a critical business application.When the person leaves, your operations can get crippled if you do not have qualified personnel who can run or resolve any issues with the application.
Protection against a single point of failure
Once you have identified SPOFs in your infrastructure, you can formulate your mitigation strategy.
SPOF protection strategy components
A typical strategy would include the following actions:
- Back up all identified systems and system components. These backups will be ready to take over the workloads of problematic systems if needed.
- Review backup, disaster recovery, and business continuity plans. The plans themselves may contain weaknesses that can lead to systems failure. When this happens, update them accordingly and make sure that the issues are addressed.
- Formulate contingency plans for internet access. Sign up with multiple ISPs if you can afford it. Although costly, having backup ISPs can help ensure continued internet access if your main ISP encounters a problem. Moreover, request your ISPs to provide you with their contingency plans in case your systems are attacked. Test these plans regularly and adjust as necessary in the face of changing conditions.
- Prepare your teams and employees to handle sensitive tasks. Other team members should be ready to take on another task previously assigned to a resource who suddenly becomes unavailable or leaves your organization.
SPOF protection strategy samples
Protection against the SPOFs mentioned in the previous section can come easily when planned for in advance.
For the single server running a mission-critical system, there are a few solutions. One is to distribute the workload over several servers. To ensure that servers do not reach their maximum capacity and fail abruptly, you can put a load balancer that distributes workloads across the servers. Having one or more failover servers that can take over workloads automatically when the main server crashes is another solution.
For the single network switch used to connect several servers, redundant network switches and connections are useful for continued access in case the main switch goes down.
For the single ISP, signing up with one or more backup ISPs means slimmer chances of your organization losing its access to the internet completely.
For the sole employee assigned to a major system, knowledge transfer sessions and rotating people so that other employees can learn about the system lessen the potential impact of sudden resignation.
Common SPOFs in businesses
The more common SPOFs that may hound a business include:
- Poor cost tracking. You may spend money unnecessarily on items that you do not need if you do not monitor your costs constantly.
- Improper costing and pricing. If you offer your products and services at lower prices to bolster your competitiveness but the costs eat into your profits (or worse, you end up not making a profit at all), your viability as a business may suffer.
- Lack of internal controls over software. This can lead to costly losses, especially if your accounting or other financial software is involved. This can even lead to employee fraud.
- Employee fraud. Among other reasons, finding that they can just do anything with software assigned for their use gives your employees opportunities to commit fraud.
- Poor management reporting. Not being able to rely on management reports means that you do not know exactly what is going on with your business.
- Lack of written business goals. If you are not reminded of your goals every now and then, you can lose sight of why you started your business in the first place.
- Bad management decisions. Your people may end up quitting if they do not like your handling of the organization.
- Negative corporate culture. Negativity in the workplace can lead to teams that perform poorly and employees who resign suddenly.
- Sudden resignation. This can hurt your operations if you have given the employee who is leaving too many responsibilities and you do not have a proper turnover plan in place.
Protect your data with Parallels RAS
As a VDI solution, Parallels RAS offers failover and load balancing capabilities.
Parallels RAS enables deployment of virtualized applications and desktops across various locations, including your own on-premises data center or private cloud, or any of the supported cloud providers such as Amazon Web Services and Microsoft Azure. This is a failover feature in case a location becomes inaccessible, you can shift your users to the other locations and ensure continued access.
Aside from failover, Parallels RAS also offers load balancing, and other features. With load balancing, Parallels RAS prevents a server from failing due to a system crash caused by workload overload. For multiple Parallels RAS gateways, high-availability load balancing (HALB) is available. HALB distributes incoming connections dynamically to healthy gateways and avoids gateways that are encountering issues.
Other noteworthy Parallels RAS features that can help reduce potential data loss are:
- Enhanced security. With Secure Sockets Layer (SSL) and Federal Information Processing Standards (FIPS) 140-2 encryption, along with multifactor and smart card authentication, Parallels RAS becomes compliant with the General Data Protection Regulation (GDPR), Health Insurance Portability and Accountability Act (HIPAA), and Payment Card Industry Data Security Standard (PCI DSS), among other standards.
- Monitoring and reporting. Parallels Ras has a monitoring and reporting service that can generate management and custom reports along with resource and traffic utilization data, among other information, that can guide your decision-making regarding your Parallels RAS environment.
To see how the platform can help in your data protection efforts,
