Fastly Outage: What Are CDNs Exactly?
June 09, 2021

Paul Davenport
AppNeta

Share this

An hour-long outage this Tuesday ground the Internet to a halt after popular Content Delivery Network (CDN) provider, Fastly, experienced a glitch that downed Reddit, Spotify, HBO Max, Shopify, Stripe and the BBC, to name just a few of properties affected.


The error brought down everything from streamers to fintech to news outlets, but fortunately only lasted about an hour, with Fastly calling the issue a "global CDN disruption," indicating that it wasn't relegated to issues at a single data center.

While this outage was frustrating for users who logged on Tuesday morning only to be greeted by a 503 error, it likely had many non-IT folks curious about CDNs and the larger Internet Infrastructure delivering their apps, sites and workflows (at least for an hour). While IT teams understand CDNs and their role in the business-critical apps employees consume, this type of outage highlights the need for end-to-end visibility.

For starters, CDNs are a critical component of the larger Internet. CDN companies operate servers around the globe that connect to improve performance and availability of web services by caching some data as close to the end user as possible. With apps now critically linked to business tasks and productivity, the most popular apps use CDN technology to provide a consistently good experience for all users. For instance, the media content you consume (ie. your New York Times front page) may be cached at a CDN server near you so that it doesn't have to be retrieved from a far-flung server every time you load a web page.

So while a page could take hundreds of milliseconds to load when it's being retrieved from a server on the other side of the world, a CDN can usually start sending the content of a page in less than 25 milliseconds when it's already been cached. This, in part, is how apps have continued to grow more complex without impacting the responsiveness for the end user.

Another way to understand CDNs is in relation to edge computing: in many enterprise contexts, CDNs are the WAN edge.

To help avoid congestion at key points in the network, teams can employ subnets (or VLANs) to help segment traffic at key locations, which can more intelligently (and predictably) route traffic to reduce the load on the larger network. In a similar fashion, enterprises can deploy CDNs that serve external requests directly without impacting the performance of the larger WAN.

So the nutshell-take here is that despite being resilient, the Internet is very much built on optimizing performance for the task at hand, with servers and data centers across the world working together to deliver content to users. While many enterprises strive to go "internet-first" in an attempt to offload the amount of physical hardware their IT teams manage directly, these teams still need visibility into the environments that help route and deliver traffic across the enterprise footprint to ensure end-user experience stays consistent. When issues like this arise, understanding the scope of the outage from an enterprise perspective allows IT teams to identify the impact to their users and business.

Gaining this visibility requires a comprehensive monitoring tool that can take a granular look at the network while at the same time putting minimal impact on network capacity itself.

Paul Davenport is Marketing Communications Manager at AppNeta
Share this

The Latest

May 25, 2022

Site reliability engineering (SRE) is fast becoming an essential aspect of modern IT operations, particularly in highly scaled, big data environments. As businesses and industries shift to the digital and embrace new IT infrastructures and technologies to remain operational and competitive, the need for a new approach for IT teams to find and manage the balance between launching new systems and features and ensuring these are intuitive, reliable, and friendly for end users has intensified as well ...

May 24, 2022

The most sophisticated observability practitioners (leaders) are able to cut downtime costs by 90%, from an estimated $23.8 million annually to just $2.5 million, compared to observability beginners, according to the State of Observability 2022 from Splunk in collaboration with the Enterprise Strategy Group. What's more, leaders in observability are more innovative and more successful at achieving digital transformation outcomes and other initiatives ...

May 23, 2022

Programmatically tracked service level indicators (SLIs) are foundational to every site reliability engineering practice. When engineering teams have programmatic SLIs in place, they lessen the need to manually track performance and incident data. They're also able to reduce manual toil because our DevOps teams define the capabilities and metrics that define their SLI data, which they collect automatically — hence "programmatic" ...

May 19, 2022

Recently, a regional healthcare organization wanted to retire its legacy monitoring tools and adopt AIOps. The organization asked Windward Consulting to implement an AIOps strategy that would help streamline its outdated and unwieldy IT system management. Our team's AIOps implementation process helped this client and can help others in the industry too. Here's what my team did ...

May 18, 2022

You've likely heard it before: every business is a digital business. However, some businesses and sectors digitize more quickly than others. Healthcare has traditionally been on the slower side of digital transformation and technology adoption, but that's changing. As healthcare organizations roll out innovations at increasing velocity, they must build a long-term strategy for how they will maintain the uptime of their critical apps and services. And there's only one tool that can ensure this continuous availability in our modern IT ecosystems. AIOps can help IT Operations teams ensure the uptime of critical apps and services ...

May 17, 2022

Between 2012 to 2015 all of the hyperscalers attempted to use the legacy APM solutions to improve their own visibility. To no avail. The problem was that none of the previous generations of APM solutions could match the scaling demand, nor could they provide interoperability due to their proprietary and exclusive agentry ...

May 16, 2022

The DevOps journey begins by understanding a team's DevOps flow and identifying precisely what tasks deliver the best return on engineers' time when automated. The rest of this blog will help DevOps team managers by outlining what jobs can — and should be automated ...

May 12, 2022

A survey from Snow Software polled more than 500 IT leaders to determine the current state of cloud infrastructure. Nearly half of the IT leaders who responded agreed that cloud was critical to operations during the pandemic with the majority deploying a hybrid cloud strategy consisting of both public and private clouds. Unsurprisingly, over the last 12 months, the majority of respondents had increased overall cloud spend — a substantial increase over the 2020 findings ...

May 11, 2022

As we all know, the drastic changes in the world have caused the workforce to take a hybrid approach over the last two years. A lot of that time, being fully remote. With the back and forth between home and office, employees need ways to stay productive and access useful information necessary to complete their daily work. The ability to obtain a holistic view of data relevant to the user and get answers to topics, no matter the worker's location, is crucial for a successful and efficient hybrid working environment ...

May 10, 2022

For the past decade, Application Performance Management has been a capability provided by a very small and exclusive set of vendors. These vendors provided a bolt-on solution that provided monitoring capabilities without requiring developers to take ownership of instrumentation and monitoring. You may think of this as a benefit, but in reality, it was not ...