How to effectively manage network failures in data centers

Blog by EXFO

Background

Data centers are essential to the seamless operation of today’s most critical applications. They support everything from AI and autonomous vehicles to financial systems, requiring high bandwidth, low latency, and extremely reliable connections. For operators, understanding the intricacies of network failures is vital to maintain uptime and ensure the efficient performance of these data hubs.

Recognizing the root of the problem

At the core of data center issues is the network infrastructure, which can harbor problems either in its components or links. Each segment, from servers to switches, plays a critical role in the network’s overall performance. For instance, servers typically connect to the network through transceivers, where optical fiber connections are preferable for speeds over 10G. However, these fibers are susceptible to contamination through human handling, leading to failures in data transmission.

Tools and techniques to diagnose issues

To prevent such network failures, it is essential to use tools like fiber inspection scopes, which allow technicians to examine the quality of optical connector endfaces. These scopes are particularly crucial because they can reveal dirt on the silica glass of fibers, which can—even in minute quantities—block light passage and disrupt connectivity.

In the realm of optical transceivers and active optical cables (AOC), issues may arise from relaxed component specifications aimed at reducing costs. To identify such problems, network testers are invaluable as they can check various parameters including optical transmission and reception power, bit-error-rate, and even the physical condition of the hardware like temperature and electrical power consumption.

Managing complex networking structures

As data traffic moves up through the network’s hierarchy, complexities increase, particularly in the switching fabric where fiber cabling connects through multiple patching racks across different locations. This setup demands structured cabling designs and often employs multi-fiber connectors like MPO, which can face issues with fiber polarity and signal loss due to high data rates.

For less complex routing, optical loss test sets (OLTS) are useful for mapping polarity and measuring power, whereas more intricate setups benefit from tools like optical fiber multimeters (OFM) and optical time-domain reflectometers (OTDR). These devices are capable of pinpointing issues such as poor splices or bends in the fiber.

Advanced troubleshooting with next-gen technologies

Data center interconnections (DCI) represent a frontier where optical and Ethernet technologies come together. Modern metro and edge applications have shifted to using coherent optics, necessitating a deep understanding of optical line systems and dense wavelength-division multiplexing (DWDM). For these sophisticated environments, operators can rely on a suite of advanced testing tools including Ethernet testers, optical spectrum analyzers (OSA), high-performance OTDRs, and dispersion testers, especially if the integrity of the optical path is under suspicion.

Conclusion

When it comes to sustaining data center uptime and performance, the critical role of testing fiber optics cannot be overstated. Getting properly equipped for a thorough testing regimen and adhering to strict maintenance protocols not only ensures data center reliability but also enhances overall efficiency. For data center operators, being equipped with the right knowledge and tools to manage network failures effectively is essential in maintaining service integrity in a demanding environment with a competitive backdrop.