Software Toolbox Technical Blog

Redundancy is a broad concept, as explored in our Demystifying Redundancy Blog. In this post, we narrow the focus on how to manage redundant OPC servers—a critical topic for ensuring reliable process communications to your HMI, SCADA, MES, Historian, etc. Redundancy is crucial because it ensures continuous operation and data integrity in the event of system failures, minimizing downtime and potential losses.

Simply deploying two OPC servers connected to your PLCs doesn’t make them redundant. We're sometimes asked about having the two OPC servers communicate and decide when to failover. That sounds good but has a flaw. If the client loses network connection to one OPC server but the two OPC servers are still communicating, and the HMI/SCADA doesn’t have any internal failover mechanism, then no failover will occur.

In a prior blog post regarding redundancy, we learned how critical it is to plan for redundancy in the Industrial Automation space. We covered how the TOP Server Media-Level Redundancy Plug-In  facilitates duplicate or backup systems used to maintain reliable communications with the critical components in your environment which in turn minimizes data loss and increases the availability of your critical industrial data.

The engineering definition of redundancy is “the inclusion of extra components which are not strictly necessary to functioning, in case of failure in other components.” In the Industrial Automation space, redundancy is critical. Not planning for redundancy can easily result in vulnerability to financial losses due to unexpected downtime. There are multiple types of redundancy in the industry. In this blog, we will be covering “Media-Level Redundancy”.

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For many industries, where having access to process data is critical, it's common to implement redundancy on many levels to ensure there is no disruption to data collection.  While there are different levels of redundancy, the one we see users most interested in is with OPC data source redundancy.

The following short video blog demonstrates step-by-step just how easy it is to configure the Cogent DataHub to handle redundant failover between OPC UA data sources, OPC DA data sources and more.

In this edition of OPC Talk with Win and Marc, we’re going to address some common questions we get about redundancy involving OPC software.  If you’re new to the industrial automation space and want to learn more about redundancy in automation in general, visit our Demystifying Redundancy in Automation blog post.

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Redundancy can mean a lot of things, as discussed in our Demystifying Redundancy Blog post.  In this blog post we want to focus more specifically on one of the use cases in that blog post:  managing redundant OPC servers.  Just having two OPC servers talking to your PLC’s does not make them redundant.  Most OPC Servers don’t have built-in methods of knowing there is another redundant OPC server instance out there.

Some HMI/SCADA systems support redundancy but sometimes it involves scripting and other custom written code.   So, in many cases, you need supplemental software to manage and optimize the connections to your two OPC servers.  Your OPC client then talks to the redundancy management software as if it is the actual OPC server.

This blog post covers some of the considerations and watch outs when choosing how to manage your OPC server redundancy.  After that we will also discuss how the Cogent DataHub can help manage your redundancy to provide high availability for your OPC server communications.

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I’ve heard from users new to the automation profession that it can be overwhelming to learn about the product technologies used in industrial automation alone, while also learning about the concepts, and having to deliver on the job results.  This is the the first post of our Automation 101 blog series which is designed to help professionals that are new to the industrial automation space whether at the start of their careers, or moving into the operations technology (OT) world from an IT or other background.

In this post, I am going to discuss redundancy.  The term is often used broadly, and sometimes it can be a simple application, but it can also quickly unravel into a complex discussion with lots of technical details, more than can be covered in a single blog post.   Whenever a client contacts us to discuss redundancy, there are many questions we ask to understand what redundancy means in their operation.

My focus will be on providing insight to the reasons why redundancy is used, the business factors that drive how far you go with redundancy, the types or levels found in automation systems, and considerations in the implementation of automation software systems.

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This is Part 9 of our “25 Things to Consider when Choosing an OPC Tunnel” series.  Will a tunneler support redundant tunnel paths?

Redundancy is typically a more complex topic than it might sound especially if your automation control architecture is extensive and has multiple layers.  Redundancy has different meanings to different people for different applications.

This blog post will outline reasons why it's important for an OPC tunneling solution to support redundant paths for applications where it is essential minimize the risks of failure when transferring your control data and what questions to ask.