Welcome!

@DXWorldExpo Authors: Pat Romanski, Elizabeth White, Liz McMillan, Yeshim Deniz, William Schmarzo

Related Topics: @DevOpsSummit, Java IoT, Linux Containers, Machine Learning , @CloudExpo, @DXWorldExpo

@DevOpsSummit: Blog Post

What If It Is the Network? Dive Deep to Find the Root Cause

How do you identify the real cause behind the network problems?

Modern Application Performance Management (APM) solutions can be tremendously helpful in delivering end-to-end visibility into the application delivery chain: across all tiers and network sections, all the way to the end user. In previous blog posts we showed how to narrow down to various root causes of the problems that the end users might experience. Those issues ranged from infrastructure through application and network, and through the end-user client application or inefficient use of the software. When the problem comes from the end user application, e.g., a Web 2.0 Web site, user experience management (UEM) solutions can offer broad analysis of possible root causes. Similarly, when an APM fault domain algorithm points to the application, the DevOps team can go deep into the actually executed code and database queries to identify the root cause of the problem.

But what do you do when your APM tool points to the network as the fault domain? How do you identify the real cause behind the network problems? Most of the APM tools stop there, forcing the network team to use separate solutions to monitor the actual network packets.

In this article we show how an Application-Aware Network Performance Management (AANPM) suite can be used to not only zero in on the network problems as the fault domain, but also dive deeper to show the actual trace of network packets in the selected context, captured back at the time when the problem happened.

Isolating Fault Domain to the Network
In one of our blog posts we wrote how Fonterra used our APM tools to identify the problem with SAP application used in the milk churn scanning process. The operations team could easily isolate the fault domain to network problems (see Figure 1); they required, however, further analysis to identify the root cause behind that network problem.

Figure 1: The performance report indicates network problems as the fault domain

In some cases information about loss rate or zero window events is enough to successfully find and resolve the problem. In general, finding the root cause may require you to analyze more detailed, packet level views in order to see exactly what is causing this network performance problem. These details can not only help to determine why we experienced packet loss or zero window events, but also whether the problem was gradually ramping up or if there was a sudden flow control blockage, which would indicate congestion.

For example, a number of users start to experience performance degradation of the service and APM points to the network as the fault domain. The detailed, packet-level analysis can show that the whole service delivery process was blocked by failed initial name resolution.

What Really Happened in the Network?
Why is detailed packet-level analysis so important when our AANPM points to the network?

Let's first consider what happens when we determine fault domain with one of the application delivery tiers. The engineers responsible for that application can start analyzing logs or, better, drill down to single transaction execution steps and often isolate the problem to the actual line of code that was causing the whole performance degradation of the whole application.

However, when our AANPM tells us it is the network, there are no logs or code execution steps to drill down to. Unless we can deliver conclusive and actionable evidence in the form of detailed, packet-level analysis, the network team might have a problem determining the root cause and may remain skeptical whether the network is at fault at all.

This is exactly what happened to one of our customers. An APM solution had correctly identified that there was a performance problem with the web server. The reports showed who was affected and where the users affected by that problem were located when the problem was occurring. The system also pointed toward the network as the primary fault domain.

The network team tried to determine the root cause of the problem. They needed packet level data for that. But, capturing all traffic with a network protocol analyzer after the incident happened not only overloaded the IT team with unnecessary data, but eventually turned out to be a hit and miss.

What the team needed were the network packets at the time the problem occurred, and only those few packets that related to the actual communication realizing affected transactions.

Figure 2: You can drill down to analyze captured network packets in the context of given user operations

For Figure 3, and further insight, click here for the full article.

More Stories By Sebastian Kruk

Sebastian Kruk is a Technical Product Strategist, Center of Excellence, at Compuware APM Business Unit.

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


DXWorldEXPO Digital Transformation Stories
DXWorldEXPO LLC announced today that Ed Featherston has been named the "Tech Chair" of "FinTechEXPO - New York Blockchain Event" of CloudEXPO's 10-Year Anniversary Event which will take place on November 12-13, 2018 in New York City. CloudEXPO | DXWorldEXPO New York will present keynotes, general sessions, and more than 20 blockchain sessions by leading FinTech experts.
Apps and devices shouldn't stop working when there's limited or no network connectivity. Learn how to bring data stored in a cloud database to the edge of the network (and back again) whenever an Internet connection is available. In his session at 17th Cloud Expo, Ben Perlmutter, a Sales Engineer with IBM Cloudant, demonstrated techniques for replicating cloud databases with devices in order to build offline-first mobile or Internet of Things (IoT) apps that can provide a better, faster user e...
Charles Araujo is an industry analyst, internationally recognized authority on the Digital Enterprise and author of The Quantum Age of IT: Why Everything You Know About IT is About to Change. As Principal Analyst with Intellyx, he writes, speaks and advises organizations on how to navigate through this time of disruption. He is also the founder of The Institute for Digital Transformation and a sought after keynote speaker. He has been a regular contributor to both InformationWeek and CIO Insight...
Bill Schmarzo, Tech Chair of "Big Data | Analytics" of upcoming CloudEXPO | DXWorldEXPO New York (November 12-13, 2018, New York City) today announced the outline and schedule of the track. "The track has been designed in experience/degree order," said Schmarzo. "So, that folks who attend the entire track can leave the conference with some of the skills necessary to get their work done when they get back to their offices. It actually ties back to some work that I'm doing at the University of ...
"Peak 10 is a national cloud data center solutions managed services provider, and part of that is disaster recovery. We see a growing trend in the industry where companies are coming to us looking for assistance in their DR strategy," stated Andrew Cole, Director of Solutions Engineering at Peak 10, in this SYS-CON.tv interview at 18th Cloud Expo, held June 7-9, 2016, at the Javits Center in New York City, NY.
Rodrigo Coutinho is part of OutSystems' founders' team and currently the Head of Product Design. He provides a cross-functional role where he supports Product Management in defining the positioning and direction of the Agile Platform, while at the same time promoting model-based development and new techniques to deliver applications in the cloud.
Andrew Keys is Co-Founder of ConsenSys Enterprise. He comes to ConsenSys Enterprise with capital markets, technology and entrepreneurial experience. Previously, he worked for UBS investment bank in equities analysis. Later, he was responsible for the creation and distribution of life settlement products to hedge funds and investment banks. After, he co-founded a revenue cycle management company where he learned about Bitcoin and eventually Ethereal. Andrew's role at ConsenSys Enterprise is a mul...
The revocation of Safe Harbor has radically affected data sovereignty strategy in the cloud. In his session at 17th Cloud Expo, Jeff Miller, Product Management at Cavirin Systems, discussed how to assess these changes across your own cloud strategy, and how you can mitigate risks previously covered under the agreement.
Digital Initiatives create new ways of conducting business, which drive the need for increasingly advanced security and regulatory compliance challenges with exponentially more damaging consequences. In the BMC and Forbes Insights Survey in 2016, 97% of executives said they expect a rise in data breach attempts in the next 12 months. Sixty percent said operations and security teams have only a general understanding of each other’s requirements, resulting in a “SecOps gap” leaving organizations u...
Cell networks have the advantage of long-range communications, reaching an estimated 90% of the world. But cell networks such as 2G, 3G and LTE consume lots of power and were designed for connecting people. They are not optimized for low- or battery-powered devices or for IoT applications with infrequently transmitted data. Cell IoT modules that support narrow-band IoT and 4G cell networks will enable cell connectivity, device management, and app enablement for low-power wide-area network IoT. B...