<img height="1" width="1" style="display:none;" alt="" src="https://px.ads.linkedin.com/collect/?pid=1110556&amp;fmt=gif">
Skip to content
    May 22, 2023

    Troubleshooting SD-WAN Performance Problems


    Software-Defined Wide Area Network (SD-WAN) technology is revolutionizing the way organizations manage their network traffic. With its ability to decouple the data plane from the control plane, SD-WAN provides organizations with a more flexible, scalable, and cost-effective solution for managing their network traffic. However, understanding and troubleshooting SD-WAN performance can be a challenge, especially when it comes to the underlying physical network, or underlay.

    In this article, we will provide an overview of SD-WAN, the importance of end-to-end underlay monitoring, and four tips for troubleshooting SD-WAN performance problems. With this information, organizations can ensure optimal performance, a positive end-user experience, and peace of mind knowing that their network is running smoothly.

    Overview of software-defined wide area networks

    SD-WAN is a technology that utilizes software to direct and enhance the flow of network traffic across WANs (Wide Area Networks). It centralizes network control and management, making it easier to operate and maintain network infrastructure, especially in complex and multi-branch setups.

    In contrast to traditional WAN solutions that rely on dedicated, hardware-based connections, SD-WAN allows companies to securely direct network traffic over various transport connections, such as broadband, LTE, and MPLS. This offers organizations the ability to choose the optimal connection for each application, resulting in improved performance and reduced reliance on costly dedicated WAN connections.

    As the use of cloud-based applications and services grows, traditional WAN solutions are becoming obsolete. SD-WAN network technology, which is flexible, scalable, and secure, enables businesses to fully utilize cloud-based services while also supporting their growth. The central management interface simplifies network administration, allowing businesses to respond quickly to changing needs. Furthermore, by utilizing multiple transport connections, SD-WAN offers a cost-effective alternative to traditional WAN solutions and assists organizations in effectively catering to their customers' needs and users' demands.

    Decoupling the data plane and control plane in SD-WAN

    One of the key benefits of SD-WAN is its ability to decouple the data plane from the control plane, which creates the notion of overlay and underlay. The overlay refers to the virtual network that is created on top of the underlying physical network (or underlay). The overlay is responsible for directing network traffic and providing centralized management and control. The underlay, on the other hand, refers to the underlying physical network infrastructure, including transport connections, switches, and routers.

    While SD-WAN provides many benefits, native SD-WAN monitoring tools are limited in their ability to provide insights into the underlay. These tools are focused on the overlay, providing information about the virtual network and the performance of specific applications. However, they do not provide visibility into the underlying physical network, making it difficult to diagnose and resolve issues related to the underlay.

    In other words, overlay metrics are not enough; you need end-to-end underlay monitoring, too. Native SD-WAN monitoring tools are focused on the overlay, so they do not provide insights into the underlay. This makes it challenging to identify and resolve network performance issues – especially those that originate from the underlay network. Therefore, it is critical to have end-to-end underlay monitoring in addition to overlay monitoring.

    To fully understand the performance of an SD-WAN network, it is important to have end-to-end underlay monitoring in addition to overlay monitoring. This provides a complete picture of the network, including the underlying physical infrastructure and the transport connections. With end-to-end underlay monitoring, organizations can identify and resolve issues related to the underlay, such as network congestion, connectivity problems, and configuration errors, helping to ensure optimal performance and a positive end-user experience.

    Tips for troubleshooting SD-WAN performance

    Dealing with SD-WAN performance problems can be challenging. Nonetheless, organizations can effectively address these challenges by implementing the four practices discussed below:

    1. Check for Configuration Errors/Changes

      One of the first steps in troubleshooting SD-WAN performance is to check for configuration errors or changes. Misconfigurations can result in security issues and poor performance. To ensure that the network is properly configured, all devices (including routers, switches, and transport connections) must be reviewed regularly. Any changes or updates should be thoroughly tested before being implemented in production to ensure that they do not cause any performance or security issues.
    2. Check for Capacity Issues

      Another potential source of SD-WAN performance issues is a lack of capacity, which occurs when transports and devices do not have enough headroom to handle the traffic. This can cause network congestion and slow performance. To address this, organizations should monitor their network capacity and plan for future needs. This includes regular monitoring of bandwidth utilization and ensuring that there is enough capacity to handle peak traffic periods.
    3. Check for ISP Issues

      Problems with SD-WAN performance may also come from third-party transport providers. In this case, it is important to analyze network paths and identify any issues with Internet Service Providers (ISPs). This includes checking for network congestion, connectivity problems, and any issues with the transport infrastructure. Regular monitoring of network paths and working with ISPs to resolve any issues can help ensure optimal network performance.
    4. Check the End-User Experience

      Finally, when troubleshooting SD-WAN performance, it is critical to consider end-user experience. Device performance metrics may not always accurately reflect the actual user experience. To ensure that end users have the best possible experience, it is critical to collect and analyze end-user feedback regularly as well as monitor device performance metrics such as latency, jitter, and packet loss. As a result, organizations can gain a better understanding of their network's overall performance and take the necessary steps to improve it.


    In conclusion, the success of SD-WAN technology depends on comprehensive performance monitoring. While overlay metrics are useful, they are insufficient for fully understanding network performance. Organizations must consider end-to-end underlay monitoring to ensure optimal network performance and a positive user experience. This comprehensive approach, combined with the four tips discussed above (checking configurations, capacity, ISPs, and end-user experience) will help organizations identify and resolve performance issues effectively. To reap the full benefits of SD-WAN, organizations must prioritize end-to-end underlay monitoring as a critical component of their network management strategy.

    Tag(s): NetOps , DX NetOps , AppNeta , SD-WAN

    Faith Kilonzi

    Faith Kilonzi is a full-stack software engineer, technical writer, and a DevOps enthusiast, with a passion for problem-solving through implementation of high-quality software products. She holds a bachelor’s degree in Computer Science from Ashesi University. She has experience working in academia, fin-tech,...

    Other posts you might be interested in

    Explore the Catalog
    December 1, 2023

    An ROI of 471%: New Study Demonstrates the Value of ValueOps

    Read More
    November 27, 2023

    ValueOps by Broadcom Delivered 471% ROI According to TEI Study

    Read More
    November 15, 2023

    Get the Maximum Value from Your ValueOps Tools

    Read More
    November 4, 2023

    Kubernetes Primer: Implementation and Administration of DX APM

    Read More
    October 31, 2023

    Got Ghosts in Your Enterprise Network?

    Read More
    October 30, 2023

    5 Ways Clarity Supercharges My Role as a Product Marketer

    Read More
    October 26, 2023

    Cloud Automation Integrations for Azure from Automation by Broadcom

    Read More
    October 25, 2023

    SD-WAN Performance and User Experience: Gaining Unified Visibility with DX NetOps

    Read More
    October 25, 2023

    Getting Started with Value Stream Management

    Read More