Uptime Institute’s Annual Outage Analysis shows that the cost of IT and data outages is increasing, and more than two-thirds of these outages cost over $100,000 in financial losses. 

There’s a simple way to mitigate these risks while minimizing financial loss and improving network efficiency — building a fully redundant network primed to handle hardware failures, software bugs, and malicious attacks. 

In this article, we’ll cover the ins and outs of network redundancy, including:

• What is network redundancy?
• Why network redundancy matters
• How network redundancy works
• Common types of network redundancy
• How to build network redundancy
• Challenges in implementing network redundancy

What is network redundancy?

Network redundancy ensures consistent network availability by duplicating critical parts. This principle of network design keeps your system running smoothly, with backup parts ready to take over if something fails. 

Think of it as a spare tire for your car—if you get a flat tire, you can quickly replace it with the spare, allowing you to continue your journey without being stranded. 

Some key components of network redundancy include:

• Failover: Automatic switch to a standby system if the primary system fails.
• Load balancing: Distributes network traffic across multiple servers to optimize resource use and prevent overload.
• Redundancy: Aims to provide automatic processes for moving to backup equipment and procedures, such as automatically moving to standby equipment that is ready to go
• Geographic redundancy: Distributes resources across different locations to protect against site-specific failures.
• High availability: Ensures system uptime and access to critical resources.

Why network redundancy matters

Network redundancy is critical because it provides these essential benefits:

• Business continuity: Keeps business operations running smoothly even when a failure occurs
• Risk management: Reduces the risk of network failure and data loss due to hardware failure, software bugs, or external attacks
• Cost savings: Reduces downtime costs and potential revenue loss from network outages
• Performance optimization: Balances network traffic to prevent overloads
• Scalability: Allows the network to handle growth and increased demand
• Disaster recovery: Provides a quick recovery path in case of major failures or disasters
• Customer satisfaction: Maintains reliable service for customers

How network redundancy works

A redundant network addresses three key areas to ensure smooth operation:

• Hardware redundancy involves duplicating physical components to prevent single points of failure. This includes having extra servers, backup power supplies, and redundant network switches.

• Software redundancy uses multiple applications on different servers or virtualization to create multiple virtual instances.

• Data redundancy involves storing copies of data in multiple locations to protect against loss or corruption. Regular backups and cloud storage are a few ways to accomplish this. 

Each type of redundancy helps maintain the availability, integrity, and reliability of a network by addressing different potential failure points.

Additionally, businesses use various technologies and protocols, including:

• Clustering groups multiple servers together, providing high availability and load balancing. For example, failover clusters switch to a backup server if one fails, while load-balancing clusters share traffic across several servers to prevent overload.

• Redundant power supplies use multiple power sources for continuous power supply.

• Redundant network links use multiple network connections to prevent a single point of failure. For example, link aggregation combines multiple network connections to act as one, increasing speed and reliability. 

• Protocols provide automatic failover and traffic distribution. Some examples include Hot Standby Router Protocol (HSRP), Virtual Router Redundancy Protocol (VRRP), and Gateway Load Balancing Protocol (GLBP).

Common types of network redundancy

Implementing different types of redundancies in a network ensures reliability and minimizes downtime. Let’s take a look at some common types: 

Primary and backup ISP connections for network redundancy

Primary and backup ISP (Internet Service Provider) connections ensure your office network remains connected to the Internet even if one connection fails. 

Your primary ISP connection handles all Internet traffic under normal circumstances. If this connection goes down due to technical issues, maintenance, or any other reason, then the backup ISP connection automatically takes over. This switch happens quickly and seamlessly so that everyone in the network stays online regardless of one connection failure. 

This setup enhances reliability for your business to keep running smoothly even during an outage with your primary ISP. With two ISP connections, you’re protected against single points of failure, reducing the risk of significant downtime that could affect your company’s performance and reputation.

Primary and hot-spare network equipment for network redundancy

Primary and hot-spare network equipment consists of immediate replacements for essential network devices – routers, switches, and firewalls – ready to go immediately in case of failure. In this setup, the primary equipment handles all network operations, while the hot-spare equipment is on standby, fully configured and able to take over instantly if the primary equipment fails. 

By having hot-spare devices on hand, you ensure that any hardware failure doesn’t disrupt your network’s performance. This setup also allows for quicker recovery times compared to waiting for repairs or replacements, thus protecting your business from prolonged outages and potential losses. In this way, your employees can continue working efficiently even when equipment fails.

Multiple spanning trees (MST)

Multiple spanning trees (MST) prevent network loops and enhance redundancy by creating multiple paths for data. 

Imagine a city's traffic system with several bridges connecting different areas. If one bridge closes, you can use another bridge to reach your destination. Similarly, MST uses multiple paths to automatically reroute data through an alternative link if a primary link fails, ensuring continuous network operation. 

This setup balances the load and reduces the risk of a single point of failure, keeping the network running smoothly.

Diverse trunking

Diverse trunking creates multiple network paths between devices, like having several lanes on a highway. If one lane is closed, cars can still travel smoothly using the other lanes.

Diverse trunking connects multiple cables or links between devices. If one link fails, traffic can still flow through the remaining links, ensuring continuous and fast communication. 

This setup increases bandwidth and reliability, preventing network slowdowns or outages.

Multi-protocol label switching (MPLS)

A highly advanced option that is less common is Multi-Protocol Label Switching (MPLS), which directs data through the most efficient routes using labels like a mail sorting system. 

Imagine sorting mail by attaching labels with delivery routes. Instead of checking the address at each stop, the label tells each post office where to send the mail next. Similarly, MPLS attaches labels to data packets, routing them based on short path labels rather than long network addresses. 

This reduces delays and speeds up data transfer. And if a path fails, MPLS quickly reroutes data using other paths, providing fast failover and optimized network performance.

How to build network redundancy

Plan and analyze

Step one is to identify critical components and assess potential vulnerabilities. A good systematic approach to accomplish this is:

• Map out your entire network, listing all devices and connections.
• Identify which components are critical for business operations, like key servers and network links.
• Analyze potential risks, such as single points of failure, by considering what would happen if each component failed.
• Prioritize components for redundancy based on their impact on the network.

In practice, this could involve creating a network diagram and highlighting crucial servers and connections. Then mark areas where a failure would majorly disrupt operations to zero in on critical components.

Since Meter designs custom networks for you, we can give you a comprehensive plan of your space with all devices and connections. With a ready-to-go network diagram, you’ll save time and make the planning and analysis step much easier. 

Implement redundant components

Now that you have a diagram of your network structure, you can start choosing the equipment you’ll use to set it up. Pick hardware and software that can support your network through the most common failures.

You might use a combination of these elements:

• Power supplies: Ensure all critical network components (servers, switches, routers) have dual power supplies connected to separate circuits and Uninterruptible Power Supplies (UPS).
• Network switches: Deploy redundant switches configured with spanning tree protocol (STP) to prevent loops and ensure failover in case one switch fails.
• Routers: Utilize dual routers in a high-availability configuration so that your network is less likely to go offline. By setting up two routers, you’ll always have one available to take over without any noticeable interruption. 
• Internet connections: Establish multiple ISP connections to ensure Internet redundancy, using load balancers or failover mechanisms to switch seamlessly between connections.
• Network cabling: Implement redundant cabling paths for critical connections to prevent a single point of failure due to physical damage or disconnection.
• Firewalls: Configure redundant firewalls in an active-passive or active-active setup to ensure security measures remain intact during failures.
• Storage systems: Redundant storage solutions keep your data accessible even if one hard drive or solid-state drive fails. The backup storage allows the system to continue operating uninterrupted in the event of hardware failures. Plus, it prevents accidental data loss.
• Servers: Use server clustering with automatic failover to distribute workloads and maintain availability if one server goes offline.
• Network load balancers: Integrate redundant load balancers to manage traffic distribution and provide fault tolerance for web and application servers.
• VPN Gateways: Set up redundant VPN gateways to maintain secure remote access even if one gateway fails.

Configure failover mechanisms

Set up automatic switching to backup systems when primary ones fail to ensure continuous network connectivity. 

Here’s how to do it:

• Identify critical systems that need failover support, like key servers and network connections.
• Set up failover clusters to automatically switch to backup servers when the primary ones fail.
• Implement redundant routing protocols like HSRP or VRRP to ensure routers can take over if the main router fails.
• Configure redundant routing to provide multiple paths for network traffic.

In a real-life scenario, this might look like a retail store setting up failover clusters for its web servers, so if one server fails, another takes over immediately. 

They might also use redundant routing to provide multiple paths for data, ensuring that customer orders are processed smoothly without any interruptions. This setup boosts customer satisfaction by maintaining high availability and reliability. 

Conduct regular testing and maintenance

Make sure redundancy systems are always ready to take over with regular checks and maintenance. Add these crucial steps to your maintenance plan: 

• Schedule routine checks to verify that backup servers, routers, and power supplies are functioning correctly.
• Perform failover tests to confirm that automatic switching works smoothly. 
• Regularly update and replace aging hardware to prevent failures. 

This proactive approach helps identify and fix issues before they cause downtime, ensuring continuous network reliability.

Monitor performance and adjust

Track the health and efficiency of your systems with network monitoring tools. 

The Meter platform includes automated network health monitoring, which notifies the support team if the network goes down for 24/7 alerts. 

Meter helps you analyze the data to identify issues or failing components and make necessary adjustments, such as replacing faulty hardware. Our software updates occur during off-hours, and hardware upgrades are part of your subscription.

Challenges in implementing network redundancy

Redundancy naturally complicates things. Extra hardware, more planning, and additional complex processes can pose challenges for businesses, like:

• Cost implications include additional hardware, software, and maintenance fees that can be significant.
• The complexity of redundancy setup requires careful planning and specialized knowledge to make sure all components work together without issue.
• Ongoing management through continuous monitoring, updates, and testing is necessary but can be a drain on time and resources. 

Balancing redundancy with cost-efficiency and performance involves strategic planning. Before you dive into creating a redundant network, consider:

• Identifying the most critical parts of your network that need redundancy.
• Investing in scalable solutions that can grow with your business.
• Prioritizing cost-effective technologies like cloud-based backups.
• Reviewing and improving your setup to make sure it meets requirements without unnecessary expenses.

Next steps: Let Meter help support your network engineers

Implementing network redundancy can save you time, money, and a whole lot of unhappy customers if your network goes down.

Meter provides an end-to-end solution that handles everything from design and installation to ongoing maintenance and support. Meter’s hardware and software capabilities support network redundancy with:

• Multi-WAN capabilities: Improves failover by spreading network traffic across all active connections using a round-robin method. This boosts network reliability, increases speed, and makes the best use of your ISP connections.
• Automatic failover: We support multiple ISPs for failover. We’ll work with you to determine which configuration is best for your company.
• Upgrades and relocations included: New hardware is included in your monthly bill. Moving to a new space? We’ll move your entire network over for free.
• 24/7 operations: Remote monitoring and consistent support means your network is always available and performant. We’ll help you sort out the small stuff with phone support and immediately send someone over to handle the tough problems. 

Try a demo of Meter and see how simple it can be to create an efficient, cost-effective redundant network.