Click here to close now.




















Welcome!

Agile Computing Authors: Greg Dickinson, Dana Gardner, Adrian Bridgwater, Tim Hinds, Jim Taylor

Related Topics: Containers Expo Blog, @CloudExpo

Containers Expo Blog: Article

Cloud Computing and Reliability

The Cloud offers some enticing advantages with respect to reliability

Eric Novikoff's Blog

IT managers and pundits speak of the reliability of a system in "nines." Two nines is the same as 99%, which comes to (100%-99%)*365 or 3.65 days of downtime per year, which is typical for non-redundant hardware if you include the time to reload the operating system and restore backups (if you have them) after a failure. Three nines is about 8 hours of downtime, four nines is about 52 minutes and the holy grail of 5 nines is 7 minutes.

From a users' point of view, downtime is downtime, but for a provider/vendor/web site manager, downtime is divided into planned and unplanned. Cloud computing can offer some benefits for planned downtime, but the place that it can have the largest effect on a business is in reducing unplanned downtime.

Planned downtime is usually the result of having to do some sort of software maintenance or release process, which is usually outside the domain of the cloud vendor, unless that vendor also offers IT operations services. Other sources of planned downtime are upgrades or scheduled equipment repairs. Most cloud vendors have some planned downtime, but because their business is based on providing high uptime, scheduled downtimes are kept to a minimum.

Unplanned downtime is where cloud vendors have the most to offer, and also the most to lose. Recent large outages at Amazon and Google have shown that even the largest cloud vendors can still have glitches that take considerable time to repair and give potential cloud customers a scare (perhaps it is because they didn't take some planned downtime??) On the other hand, cloud vendors have the experienced staff and proven processes that should produce overall hardware and network reliability that meets or exceeds that of the average corporate data center, and far exceeds anything you can achieve with colocated or self-managed servers.

However, despite claims of reliablity, few cloud vendors have tight SLAs (service level agreements) that promise controlled downtime or offer rebates for excess downtime. Amazon goes the opposite direction and doesn't offer any uptime guarantees, even cautioning users that their instance (or server) can disappear at any time and that they should plan accordingly. AppLogic-based clouds, provided by companies such as ENKI, are capable of offering better guarantees of uptime because of its inherent self-healing capabilities that can enable 3-4 nines of uptime. (The exact number depends on how the AppLogic system is set up and administered, which affects the time needed for the system to heal itself.) However, any cloud computing system, even even those based on AppLogic or similar technologies, can experience unplanned downtime for a variety of reasons, including the common culprit of human error. While I believe it is possible to produce a cloud computing service that exceeds 4-9s of uptime, the costs would be so high that few would buy it when they compared the price to the average cloud offering.


When you're purchasing cloud computing, it makes sense to look at the SLA of the vendor as well as the reliability of the underlying technology. But if your needs for uptime exceed that which the vendors and their technology can offer, there are time-honored techniques for improving it, most of which involve doubling the amount of computing nodes in your application. There's an old adage that each additional "9" of uptime you get doubles your cost, and that's because you need backup systems that are in place to take over if the primaries fail. This involves creating a system architecture for your application that allows for either active/passive failover (meaning that the backup nodes are running but not doing anything) or active/active failover (meaning that the backup nodes are normally providing application computing capability).

These solutions can be implemented in any cloud technology but they always require extra design and configuration effort for your application, and they should be tested rigorously to make sure they will work when the chips are down. Failover solutions are generally less expensive to implement in the Cloud because of the on-demand or pay-as-you go nature of cloud services, which means that you can easily size the backup server nodes to meet your needs and save on computing resources.

An important component of reliability is a good backup strategy. With cloud computing systems like AppLogic offering highly reliable storage as part of the package, many customers are tempted to skip backup. But data loss and the resulting unplanned downtime can result not just from failures in the cloud platform, but also software bugs, human error, or malfeasance such as hacking. If you don't have a backup, you'll be down a long time - and this applies equally to cloud and non-cloud solutions. The advantages of cloud solutions is that there is usually an inexpensive and large storage facility coupled with the cloud computing offering which gives you a convenient place to store your backups.

For the truly fanatical, backing up your data from one cloud vendor to another provides that extra measure of security. It pays to think through your backup strategy because most of today's backup software packages or remote backup services were designed for physical servers and not virtual environments having many virtual servers such as you might find in the cloud. This can mean very high software costs for doing backup if your backup software charges on a "per server" basis and your application is spread across many instances. If your cloud vendor has a backup offering, usually they have found a way to make backup affordable even if your application consists of many compute instances.

Another aspect of reliability that often escapes cloud computing customers new to the world of computing services is monitoring. It's very hard to react to unplanned downtime if you don't know your system is down. It's also hard to avoid unplanned downtime if you don't know you're about to run out of disk space or memory, or perhaps your application is complaining about data corruption. A remote monitoring service can scan your servers in the cloud on a regular basis for faults, application problems, or even measure the performance of your application (like how long it takes to buy a widget in your web store) and report to you if anything is out of the ordinary. I say "service" because if you were to install your own monitoring server into your cloud and the cloud went down, so would your monitoring! At ENKI, we solve this problem by having our monitoring service hosted in a separate data center and under a different software environment than our primary cloud hosting service.

The last aspect of reliability is security. However, that would require another entire article to cover, since security in the cloud is a complex and relatively new topic.

To sum up, the Cloud offers some enticing advantages with respect to reliability, perhaps the largest of which is that you can give your data center operations responsibility to someone who theoretically can do a much better job at a lower cost than you can. However, to get very good reliability, you must still apply traditional approaches of redundancy and observability that have been used in physical data centers for decades - or, you have to find a cloud computing services provider that can implement them for you.

More Stories By Eric Novikoff

Eric Novikoff is COO of ENKI, A Cloud Services Vendor. He has over 20 years of experience in the electronics and software industries, over a range of positions from integrated circuit designer to software/hardware project manager, to Director of Development at an Internet Software As A Service startup, Netsuite.com. His technical, project, and financial management skills have been honed in multiple positions at Hewlett-Packard and Agilent Technologies on a variety of product lines, including managing the development and roll-out of a worldwide CRM and sales automation application for Agilent's $350 million Automatic Test Equipment business. Novikoff also has a strong interest in SME (Small/Medium Size Enterprise) management, process development, and operations as a consequence of working at a web based ERP service startup serving SMEs, and through his small-business ERP consulting work.

Comments (1) View Comments

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.


Most Recent Comments
faseidl 09/10/08 11:45:52 AM EDT

Despite what many pundits have to say, reliability issues will not be the downfall of cloud computing. Using cloud computing does not mean neglecting to architect solutions that meet their business requirements, including reliability requirements.

I wrote more about this idea here:

Cloud Computing and Reliability
http://faseidl.com/public/item/212584

@ThingsExpo Stories
SYS-CON Events announced today that HPM Networks will exhibit at the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. For 20 years, HPM Networks has been integrating technology solutions that solve complex business challenges. HPM Networks has designed solutions for both SMB and enterprise customers throughout the San Francisco Bay Area.
For IoT to grow as quickly as analyst firms’ project, a lot is going to fall on developers to quickly bring applications to market. But the lack of a standard development platform threatens to slow growth and make application development more time consuming and costly, much like we’ve seen in the mobile space. In his session at @ThingsExpo, Mike Weiner, Product Manager of the Omega DevCloud with KORE Telematics Inc., discussed the evolving requirements for developers as IoT matures and conducted a live demonstration of how quickly application development can happen when the need to comply wit...
The Internet of Everything (IoE) brings together people, process, data and things to make networked connections more relevant and valuable than ever before – transforming information into knowledge and knowledge into wisdom. IoE creates new capabilities, richer experiences, and unprecedented opportunities to improve business and government operations, decision making and mission support capabilities.
Explosive growth in connected devices. Enormous amounts of data for collection and analysis. Critical use of data for split-second decision making and actionable information. All three are factors in making the Internet of Things a reality. Yet, any one factor would have an IT organization pondering its infrastructure strategy. How should your organization enhance its IT framework to enable an Internet of Things implementation? In his session at @ThingsExpo, James Kirkland, Red Hat's Chief Architect for the Internet of Things and Intelligent Systems, described how to revolutionize your archit...
MuleSoft has announced the findings of its 2015 Connectivity Benchmark Report on the adoption and business impact of APIs. The findings suggest traditional businesses are quickly evolving into "composable enterprises" built out of hundreds of connected software services, applications and devices. Most are embracing the Internet of Things (IoT) and microservices technologies like Docker. A majority are integrating wearables, like smart watches, and more than half plan to generate revenue with APIs within the next year.
Growth hacking is common for startups to make unheard-of progress in building their business. Career Hacks can help Geek Girls and those who support them (yes, that's you too, Dad!) to excel in this typically male-dominated world. Get ready to learn the facts: Is there a bias against women in the tech / developer communities? Why are women 50% of the workforce, but hold only 24% of the STEM or IT positions? Some beginnings of what to do about it! In her Opening Keynote at 16th Cloud Expo, Sandy Carter, IBM General Manager Cloud Ecosystem and Developers, and a Social Business Evangelist, d...
In his keynote at 16th Cloud Expo, Rodney Rogers, CEO of Virtustream, discussed the evolution of the company from inception to its recent acquisition by EMC – including personal insights, lessons learned (and some WTF moments) along the way. Learn how Virtustream’s unique approach of combining the economics and elasticity of the consumer cloud model with proper performance, application automation and security into a platform became a breakout success with enterprise customers and a natural fit for the EMC Federation.
The Internet of Things is not only adding billions of sensors and billions of terabytes to the Internet. It is also forcing a fundamental change in the way we envision Information Technology. For the first time, more data is being created by devices at the edge of the Internet rather than from centralized systems. What does this mean for today's IT professional? In this Power Panel at @ThingsExpo, moderated by Conference Chair Roger Strukhoff, panelists addressed this very serious issue of profound change in the industry.
Discussions about cloud computing are evolving into discussions about enterprise IT in general. As enterprises increasingly migrate toward their own unique clouds, new issues such as the use of containers and microservices emerge to keep things interesting. In this Power Panel at 16th Cloud Expo, moderated by Conference Chair Roger Strukhoff, panelists addressed the state of cloud computing today, and what enterprise IT professionals need to know about how the latest topics and trends affect their organization.
It is one thing to build single industrial IoT applications, but what will it take to build the Smart Cities and truly society-changing applications of the future? The technology won’t be the problem, it will be the number of parties that need to work together and be aligned in their motivation to succeed. In his session at @ThingsExpo, Jason Mondanaro, Director, Product Management at Metanga, discussed how you can plan to cooperate, partner, and form lasting all-star teams to change the world and it starts with business models and monetization strategies.
Converging digital disruptions is creating a major sea change - Cisco calls this the Internet of Everything (IoE). IoE is the network connection of People, Process, Data and Things, fueled by Cloud, Mobile, Social, Analytics and Security, and it represents a $19Trillion value-at-stake over the next 10 years. In her keynote at @ThingsExpo, Manjula Talreja, VP of Cisco Consulting Services, discussed IoE and the enormous opportunities it provides to public and private firms alike. She will share what businesses must do to thrive in the IoE economy, citing examples from several industry sectors.
There will be 150 billion connected devices by 2020. New digital businesses have already disrupted value chains across every industry. APIs are at the center of the digital business. You need to understand what assets you have that can be exposed digitally, what their digital value chain is, and how to create an effective business model around that value chain to compete in this economy. No enterprise can be complacent and not engage in the digital economy. Learn how to be the disruptor and not the disruptee.
Akana has released Envision, an enhanced API analytics platform that helps enterprises mine critical insights across their digital eco-systems, understand their customers and partners and offer value-added personalized services. “In today’s digital economy, data-driven insights are proving to be a key differentiator for businesses. Understanding the data that is being tunneled through their APIs and how it can be used to optimize their business and operations is of paramount importance,” said Alistair Farquharson, CTO of Akana.
Business as usual for IT is evolving into a "Make or Buy" decision on a service-by-service conversation with input from the LOBs. How does your organization move forward with cloud? In his general session at 16th Cloud Expo, Paul Maravei, Regional Sales Manager, Hybrid Cloud and Managed Services at Cisco, discusses how Cisco and its partners offer a market-leading portfolio and ecosystem of cloud infrastructure and application services that allow you to uniquely and securely combine cloud business applications and services across multiple cloud delivery models.
The enterprise market will drive IoT device adoption over the next five years. In his session at @ThingsExpo, John Greenough, an analyst at BI Intelligence, division of Business Insider, analyzed how companies will adopt IoT products and the associated cost of adopting those products. John Greenough is the lead analyst covering the Internet of Things for BI Intelligence- Business Insider’s paid research service. Numerous IoT companies have cited his analysis of the IoT. Prior to joining BI Intelligence, he worked analyzing bank technology for Corporate Insight and The Clearing House Payment...
"Optimal Design is a technology integration and product development firm that specializes in connecting devices to the cloud," stated Joe Wascow, Co-Founder & CMO of Optimal Design, in this SYS-CON.tv interview at @ThingsExpo, held June 9-11, 2015, at the Javits Center in New York City.
SYS-CON Events announced today that CommVault has been named “Bronze Sponsor” of SYS-CON's 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. A singular vision – a belief in a better way to address current and future data management needs – guides CommVault in the development of Singular Information Management® solutions for high-performance data protection, universal availability and simplified management of data on complex storage networks. CommVault's exclusive single-platform architecture gives companies unp...
Electric Cloud and Arynga have announced a product integration partnership that will bring Continuous Delivery solutions to the automotive Internet-of-Things (IoT) market. The joint solution will help automotive manufacturers, OEMs and system integrators adopt DevOps automation and Continuous Delivery practices that reduce software build and release cycle times within the complex and specific parameters of embedded and IoT software systems.
"ciqada is a combined platform of hardware modules and server products that lets people take their existing devices or new devices and lets them be accessible over the Internet for their users," noted Geoff Engelstein of ciqada, a division of Mars International, in this SYS-CON.tv interview at @ThingsExpo, held June 9-11, 2015, at the Javits Center in New York City.
Internet of Things is moving from being a hype to a reality. Experts estimate that internet connected cars will grow to 152 million, while over 100 million internet connected wireless light bulbs and lamps will be operational by 2020. These and many other intriguing statistics highlight the importance of Internet powered devices and how market penetration is going to multiply many times over in the next few years.