Welcome!

Weblogic Authors: Yeshim Deniz, Elizabeth White, Michael Meiner, Michael Bushong, Avi Rosenthal

Related Topics: @CloudExpo, Microservices Expo

@CloudExpo: Article

Lessons from the Amazon Cloud Outage

Best Practices for Resilient Cloud Applications

As reported in SYS-CON and elsewhere, we found the Amazon's cloud crashed, taking sites like Reddit, Foursquare, Quora, Hootsuite, Indaba, GroupMe, Scvngr, Motherboard.tv and few more down with it.

As reported several components of Amazon Cloud portfolio like, EC2, Elastic Block Store (EBS), Relational Database Service (RDS), Elastic Beastalk, CloudFormation and lately MapReduce were all impacted.

Amazon has given the following explanation for the crash at this time:

"A networking event triggered a large amount of re-mirroring of EBS [Extended Block Store] volumes ... This re-mirroring created a shortage of capacity ... which impacted new EBS volume creation as well as the pace with which we could re-mirror and recover affected EBS volumes."

While this issue will be solved for now, this has created a huge impact on the Cloud Adoption for the large enterprises. However, the traditional high availability best practices always hold good for Cloud also and this issue cannot be seen as the failure of Cloud, rather more on the implementation. The following best practices will guard the cloud applications on top of the out of the box high availability options provided by the Cloud Provider like Amazon.

Ensure Application Controlled Scalability
We have got components like Auto Scaling, Elastic Load Balancing and Cloud Watch etc... These will help the scalability by monitoring the resource usage and automatically allocate new instances.

However this is achieved, if the application is aware of its usage and scales accordingly.

One such implementation pattern is a Routing Server, where the application characteristic like the type of the user, geography or the kind of transaction determines the target destination to be process the request and load balance accordingly.

Making the data aware scaling rules configurable without restarting the servers will go a long way in adjusting the routing mechanism to specific servers in case of regions or availability Zones are down due to the unknown reasons. This will also ensure that scalability rules can be dynamically altered in cases of catastrophic situations, such that some high priority transactions can continue to be served and low-priority transactions can be put on hold.

Stay Disconnected
Even though the typical application consists of multiple logical and physical components, it is best to decouple each of these components, so that each layer interacts with the   next layer in an asynchronous manner.

While there are some applications like banking, stock trading and online reservation which requires real time and stay connected nature, most applications in today's scenario can still take the advantage of a disconnected architecture.

Use reliable messaging and request / response framework so that the end users are never aware that their request is queued rather they get a feeling that their request is taken care and got a satisfactory response. This will ensure that even if some physical servers or logical components are down we can still not impact the end user.

Keep Transactions Smaller
The best path to ensure transparent application fail over and recoverability is to ensure that the transactions are as small as possible, and each step ensures a logically meaningful step within the overall process from an end-user perspective.

Remember some legacy applications of the previous era, which accepts transaction data for several fields and pages and used to have a Single SAVE button, and if anything happens, the end user lost all the data requiring to be re-entered, this needs to be avoided at all cost and the systems should be designed to be a combination of logically smaller steps that tied together in a loose coupled manner.

VEET: The User Entered Data
In a disconnected environment, end users are not there to fix the data entry errors or provide additional information, so that best fault tolerant systems are designed when the user is made to enter minimal data and the pattern of VEET (Validate Extract Enrich Transform) is applied to the user data.

Validate: Once the transaction inputs are entered and accepted, they stay as a meaningful information across the system components and no need to correct any data.

Extract: Never accept the information which can be derived, this will ensure that the errors are avoided on the known data.

Enrich: Accumulate the information from the existing information, so that the information need not be entered by the user. For example if the user enters the zipcode, the City, state and other information can automatically be retrieved.

Transform: Transform from one form to another form as it is meaningful to the system flow.

The above steps ensure that we can recover gracefully from failures, which will be transparent to the user.

Keep the Backup Data to the Lowest Granularity for Recovery
We have seen the storage mechanisms like Amazon EBS (Amazon Elastic Block Store) have in built fault tolerant mechanism such that volumes are replicated automatically. This is a very good feature. But more the data is backup as a raw volumes, we should also think about the ability to quickly recover and get going in case of disasters.

Typically database instances take some time to recover the pending transactions or to roll back the unfinished ones, proper backup mechanisms can help to recover from this scenario quickly.

The following options can be considered in the order to quickly recover from a disaster scenario.

Alternative Write Mechanism: Whether a log shipping or stand by database or simply mirror the data to other availability zones is one of the best mechanism to keep the databases in sync and quickly recover when one zone is not available.

Implicit Raw Volume Backups: This is employed out of the box in most of the cloud platform, however the intelligence to quickly recover the raw volumes with automated scripts should be in place.

Share Nothing
From the Amazon experience it is clear that in spite of the best availability mechanisms adopted by the Cloud provider, rarely we may end up in few availability zones struck by disaster.

However, during these scenarios we wanted to ensure that not all our users are affected, but only the minimal number of users. This can be achieved by adopting the ‘Shared Nothing Pattern' so that tenants are logically and physically separate within the Cloud Eco System.

This will ensure that the failure of part of the infrastructure will not affect everyone in the system.

Summary
The Amazon Cloud down event is a wake-up call about how Cloud can be utilized. There is no automatic switch that ensures all the fault tolerant needed for the systems. However, this has reinforced the strong fundamental principles with which applications needs to be built in order to be resilient. This incident cannot be seen as a failure of the Cloud platform itself and we have lot of room for improvement and to avoid these situations in future.

More Stories By Srinivasan Sundara Rajan

Highly passionate about utilizing Digital Technologies to enable next generation enterprise. Believes in enterprise transformation through the Natives (Cloud Native & Mobile Native).

@ThingsExpo Stories
As popularity of the smart home is growing and continues to go mainstream, technological factors play a greater role. The IoT protocol houses the interoperability battery consumption, security, and configuration of a smart home device, and it can be difficult for companies to choose the right kind for their product. For both DIY and professionally installed smart homes, developers need to consider each of these elements for their product to be successful in the market and current smart homes.
Widespread fragmentation is stalling the growth of the IIoT and making it difficult for partners to work together. The number of software platforms, apps, hardware and connectivity standards is creating paralysis among businesses that are afraid of being locked into a solution. EdgeX Foundry is unifying the community around a common IoT edge framework and an ecosystem of interoperable components.
Join IBM November 1 at 21st Cloud Expo at the Santa Clara Convention Center in Santa Clara, CA, and learn how IBM Watson can bring cognitive services and AI to intelligent, unmanned systems. Cognitive analysis impacts today’s systems with unparalleled ability that were previously available only to manned, back-end operations. Thanks to cloud processing, IBM Watson can bring cognitive services and AI to intelligent, unmanned systems. Imagine a robot vacuum that becomes your personal assistant th...
SYS-CON Events announced today that Avere Systems, a leading provider of hybrid cloud enablement solutions, will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Avere Systems was created by file systems experts determined to reinvent storage by changing the way enterprises thought about and bought storage resources. With decades of experience behind the company’s founders, Avere got its ...
SYS-CON Events announced today that Golden Gate University will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Since 1901, non-profit Golden Gate University (GGU) has been helping adults achieve their professional goals by providing high quality, practice-based undergraduate and graduate educational programs in law, taxation, business and related professions. Many of its courses are taug...
SYS-CON Events announced today that SIGMA Corporation will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. uLaser flow inspection device from the Japanese top share to Global Standard! Then, make the best use of data to flip to next page. For more information, visit http://www.sigma-k.co.jp/en/.
High-velocity engineering teams are applying not only continuous delivery processes, but also lessons in experimentation from established leaders like Amazon, Netflix, and Facebook. These companies have made experimentation a foundation for their release processes, allowing them to try out major feature releases and redesigns within smaller groups before making them broadly available. In his session at 21st Cloud Expo, Brian Lucas, Senior Staff Engineer at Optimizely, will discuss how by using...
In this strange new world where more and more power is drawn from business technology, companies are effectively straddling two paths on the road to innovation and transformation into digital enterprises. The first path is the heritage trail – with “legacy” technology forming the background. Here, extant technologies are transformed by core IT teams to provide more API-driven approaches. Legacy systems can restrict companies that are transitioning into digital enterprises. To truly become a lead...
SYS-CON Events announced today that CAST Software will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 - Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. CAST was founded more than 25 years ago to make the invisible visible. Built around the idea that even the best analytics on the market still leave blind spots for technical teams looking to deliver better software and prevent outages, CAST provides the software intelligence that matter ...
SYS-CON Events announced today that Daiya Industry will exhibit at the Japanese Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Ruby Development Inc. builds new services in short period of time and provides a continuous support of those services based on Ruby on Rails. For more information, please visit https://github.com/RubyDevInc.
As businesses evolve, they need technology that is simple to help them succeed today and flexible enough to help them build for tomorrow. Chrome is fit for the workplace of the future — providing a secure, consistent user experience across a range of devices that can be used anywhere. In her session at 21st Cloud Expo, Vidya Nagarajan, a Senior Product Manager at Google, will take a look at various options as to how ChromeOS can be leveraged to interact with people on the devices, and formats th...
SYS-CON Events announced today that Yuasa System will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Yuasa System is introducing a multi-purpose endurance testing system for flexible displays, OLED devices, flexible substrates, flat cables, and films in smartphones, wearables, automobiles, and healthcare.
SYS-CON Events announced today that Taica will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Taica manufacturers Alpha-GEL brand silicone components and materials, which maintain outstanding performance over a wide temperature range -40C to +200C. For more information, visit http://www.taica.co.jp/english/.
SYS-CON Events announced today that SourceForge has been named “Media Sponsor” of SYS-CON's 21st International Cloud Expo, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. SourceForge is the largest, most trusted destination for Open Source Software development, collaboration, discovery and download on the web serving over 32 million viewers, 150 million downloads and over 460,000 active development projects each and every month.
SYS-CON Events announced today that Nihon Micron will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Nihon Micron Co., Ltd. strives for technological innovation to establish high-density, high-precision processing technology for providing printed circuit board and metal mount RFID tags used for communication devices. For more inf...
Enterprises have taken advantage of IoT to achieve important revenue and cost advantages. What is less apparent is how incumbent enterprises operating at scale have, following success with IoT, built analytic, operations management and software development capabilities – ranging from autonomous vehicles to manageable robotics installations. They have embraced these capabilities as if they were Silicon Valley startups. As a result, many firms employ new business models that place enormous impor...
SYS-CON Events announced today that MIRAI Inc. will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. MIRAI Inc. are IT consultants from the public sector whose mission is to solve social issues by technology and innovation and to create a meaningful future for people.
SYS-CON Events announced today that Dasher Technologies will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 - Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Dasher Technologies, Inc. ® is a premier IT solution provider that delivers expert technical resources along with trusted account executives to architect and deliver complete IT solutions and services to help our clients execute their goals, plans and objectives. Since 1999, we'v...
SYS-CON Events announced today that TidalScale, a leading provider of systems and services, will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 - Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. TidalScale has been involved in shaping the computing landscape. They've designed, developed and deployed some of the most important and successful systems and services in the history of the computing industry - internet, Ethernet, operating s...
SYS-CON Events announced today that Massive Networks, that helps your business operate seamlessly with fast, reliable, and secure internet and network solutions, has been named "Exhibitor" of SYS-CON's 21st International Cloud Expo ®, which will take place on Oct 31 - Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. As a premier telecommunications provider, Massive Networks is headquartered out of Louisville, Colorado. With years of experience under their belt, their team of...