Welcome!

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

Related Topics: @CloudExpo

@CloudExpo: Article

Amazon’s Elastic Block Store Opens Up S3 and The Cloud

The Big SAN in the Sky

With EBS volumes up to 1TB in size and beyond in a file system is possible to mount quickly – and multiple volumes on the same instance, such that file systems of 10TB are practical. The volumes can further be backed-up to S3 using snapshots, and they can be replicated by creating new volumes from the snapshots. What is particularly nice is that a volume can be created in any availability zone (think datacenter) of a region from a snapshot, so copying a large volume across datacenters can be off-loaded to EBS and is done very efficiently.

Incremental snapshotting of volumes and freezing
I mentioned that snapshots were a very useful but also a complex, difficult to understand feature. I wanted to explain how snapshots of an EBS volume can be taken at any time, and why using RightScale’s scripts to freeze data are important -- and a great add-on to this important feature.

Taking a snapshot causes the data on the volume to be written to S3 where it is stored redundantly in multiple availability zones as all data in S3 is. It’s worth noting snapshots do not appear in your S3 buckets, thus you can't access them using the standard S3 API. You can only list the snapshots using the EC2 API and you can restore a snapshot by creating a new volume from it.

The second thing is that snapshots are incremental, which means that in order to create a snapshot, EBS saves only the disk blocks that have changed to S3.

Each volume is divided up into blocks. When the first snapshot of a volume is taken, all blocks of the volume that have ever been written are copied to S3, and then a snapshot table of contents is written to S3 that lists all these blocks. Now, when the second snapshot is taken of the same volume, only the blocks that have changed since the first snapshot are copied to S3. The table of contents for the second snapshot is then written to S3 and lists all the blocks on S3 that belong to the snapshot. Some are shared with the first snapshot, some are new. The third snapshot is created similarly and can contain blocks copied to S3 for the first, second and third snapshots.

There are two nice things about the incremental nature of the snapshots: it saves time and space. Taking subsequent snapshots can be very fast because only changed blocks need to be sent to S3, and it saves time because you're only paying for the storage in S3 of the incremental blocks. What is difficult to answer is how much space a snapshot uses. Or, to put it differently, how much space would be saved if a snapshot were deleted. If you delete a snapshot, only the blocks that are only used by that snapshot (i.e. are only referenced by that snapshot's table of contents) are deleted.

Something to be very careful about with snapshots is consistency. A snapshot is taken at a precise moment in time even though the blocks may trickle out to S3 over many minutes. But in most situations you will really want to control what's on disk vs. what's in-flight at the moment of the snapshot. This is particularly important when using a database. We recommend you freeze the database (or any application writing critical data to disk), freeze the file system, take the snapshot, then unfreeze everything. At the file system level we've been using xfs for all the large local drives and EBS volumes because it's fast to format and supports freezing. Thus when taking a snapshot we perform an xfs freeze, take the snapshot, and unfreeze. All this ensures that the snapshot doesn't contain partial updates that need to be recovered when the snapshot is mounted.

With support for large datasets, attachments, better throughput, snapshotting and more robust, incremental backups and redundancy, Amazon’s EBS should attract a lot more enterprise and on-demand customers, as well as Web 2.0 users with large database-driven applications.

Thorsten von Eicken is RightScale, Inc.’s Chief Technical Officer. To try out a free developer version of RightScale, visit http://www.rightscale.com/m/products.html#developer.

More Stories By Thorsten von Eicken

Thorsten von Eicken is the CTO and a founder of RightScale and is responsible for the overall technology direction of the RightScale Cloud Management Platform. Previously, he was founder and chief architect at Expertcity (acquired by Citrix Online), where he directed the architecture of the company's online services, including the popular GoToMeeting service. von Eicken also managed the Expertcity/Citrix data center operations, where he acquired deep knowledge in deploying and running secure, scalable online services. He was a professor of Computer Science at Cornell University and received his Ph.D. from the University of California, Berkeley.

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
Jeremy Geelan 08/21/08 02:03:47 PM EDT

Dr von Eicken will be giving a technical session at SYS-CON's "Cloud Computing Expo" (November 19-21, 2008) - a major adjunct to the 4th International Virtualization Conference & Expo being held at The Fairmont Hotel in San Jose, CA - in which he will distill the unique characteristics of clouds and describe how to best think about deployments in the clouds.

@ThingsExpo Stories
When shopping for a new data processing platform for IoT solutions, many development teams want to be able to test-drive options before making a choice. Yet when evaluating an IoT solution, it’s simply not feasible to do so at scale with physical devices. Building a sensor simulator is the next best choice; however, generating a realistic simulation at very high TPS with ease of configurability is a formidable challenge. When dealing with multiple application or transport protocols, you would be...
Detecting internal user threats in the Big Data eco-system is challenging and cumbersome. Many organizations monitor internal usage of the Big Data eco-system using a set of alerts. This is not a scalable process given the increase in the number of alerts with the accelerating growth in data volume and user base. Organizations are increasingly leveraging machine learning to monitor only those data elements that are sensitive and critical, autonomously establish monitoring policies, and to detect...
In his keynote at 18th Cloud Expo, Andrew Keys, Co-Founder of ConsenSys Enterprise, provided an overview of the evolution of the Internet and the Database and the future of their combination – the Blockchain. 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 settl...
In his session at @ThingsExpo, Dr. Robert Cohen, an economist and senior fellow at the Economic Strategy Institute, presented the findings of a series of six detailed case studies of how large corporations are implementing IoT. The session explored how IoT has improved their economic performance, had major impacts on business models and resulted in impressive ROIs. The companies covered span manufacturing and services firms. He also explored servicification, how manufacturing firms shift from se...
DevOpsSummit New York 2018, colocated with CloudEXPO | DXWorldEXPO New York 2018 will be held November 11-13, 2018, in New York City. Digital Transformation (DX) is a major focus with the introduction of DXWorldEXPO within the program. Successful transformation requires a laser focus on being data-driven and on using all the tools available that enable transformation if they plan to survive over the long term. A total of 88% of Fortune 500 companies from a generation ago are now out of bus...
The Jevons Paradox suggests that when technological advances increase efficiency of a resource, it results in an overall increase in consumption. Writing on the increased use of coal as a result of technological improvements, 19th-century economist William Stanley Jevons found that these improvements led to the development of new ways to utilize coal. In his session at 19th Cloud Expo, Mark Thiele, Chief Strategy Officer for Apcera, compared the Jevons Paradox to modern-day enterprise IT, examin...
IoT solutions exploit operational data generated by Internet-connected smart “things” for the purpose of gaining operational insight and producing “better outcomes” (for example, create new business models, eliminate unscheduled maintenance, etc.). The explosive proliferation of IoT solutions will result in an exponential growth in the volume of IoT data, precipitating significant Information Governance issues: who owns the IoT data, what are the rights/duties of IoT solutions adopters towards t...
Amazon started as an online bookseller 20 years ago. Since then, it has evolved into a technology juggernaut that has disrupted multiple markets and industries and touches many aspects of our lives. It is a relentless technology and business model innovator driving disruption throughout numerous ecosystems. Amazon’s AWS revenues alone are approaching $16B a year making it one of the largest IT companies in the world. With dominant offerings in Cloud, IoT, eCommerce, Big Data, AI, Digital Assista...
Organizations planning enterprise data center consolidation and modernization projects are faced with a challenging, costly reality. Requirements to deploy modern, cloud-native applications simultaneously with traditional client/server applications are almost impossible to achieve with hardware-centric enterprise infrastructure. Compute and network infrastructure are fast moving down a software-defined path, but storage has been a laggard. Until now.
Digital Transformation is much more than a buzzword. The radical shift to digital mechanisms for almost every process is evident across all industries and verticals. This is often especially true in financial services, where the legacy environment is many times unable to keep up with the rapidly shifting demands of the consumer. The constant pressure to provide complete, omnichannel delivery of customer-facing solutions to meet both regulatory and customer demands is putting enormous pressure on...
In his general session at 19th Cloud Expo, Manish Dixit, VP of Product and Engineering at Dice, discussed how Dice leverages data insights and tools to help both tech professionals and recruiters better understand how skills relate to each other and which skills are in high demand using interactive visualizations and salary indicator tools to maximize earning potential. Manish Dixit is VP of Product and Engineering at Dice. As the leader of the Product, Engineering and Data Sciences team at D...
DXWorldEXPO LLC announced today that All in Mobile, a mobile app development company from Poland, will exhibit at the 22nd International CloudEXPO | DXWorldEXPO. All In Mobile is a mobile app development company from Poland. Since 2014, they maintain passion for developing mobile applications for enterprises and startups worldwide.
"Akvelon is a software development company and we also provide consultancy services to folks who are looking to scale or accelerate their engineering roadmaps," explained Jeremiah Mothersell, Marketing Manager at Akvelon, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
DXWorldEXPO LLC announced today that the upcoming DXWorldEXPO | CloudEXPO New York event will feature 10 companies from Poland to participate at the "Poland Digital Transformation Pavilion" on November 12-13, 2018.
IoT is at the core or many Digital Transformation initiatives with the goal of re-inventing a company's business model. We all agree that collecting relevant IoT data will result in massive amounts of data needing to be stored. However, with the rapid development of IoT devices and ongoing business model transformation, we are not able to predict the volume and growth of IoT data. And with the lack of IoT history, traditional methods of IT and infrastructure planning based on the past do not app...
22nd International Cloud Expo, taking place June 5-7, 2018, at the Javits Center in New York City, NY, and co-located with the 1st DXWorld Expo will feature technical sessions from a rock star conference faculty and the leading industry players in the world. Cloud computing is now being embraced by a majority of enterprises of all sizes. Yesterday's debate about public vs. private has transformed into the reality of hybrid cloud: a recent survey shows that 74% of enterprises have a hybrid cloud ...
@DevOpsSummit at Cloud Expo, taking place November 12-13 in New York City, NY, is co-located with 22nd international CloudEXPO | first international DXWorldEXPO and will feature technical sessions from a rock star conference faculty and the leading industry players in the world.
More and more brands have jumped on the IoT bandwagon. We have an excess of wearables – activity trackers, smartwatches, smart glasses and sneakers, and more that track seemingly endless datapoints. However, most consumers have no idea what “IoT” means. Creating more wearables that track data shouldn't be the aim of brands; delivering meaningful, tangible relevance to their users should be. We're in a period in which the IoT pendulum is still swinging. Initially, it swung toward "smart for smart...
As data explodes in quantity, importance and from new sources, the need for managing and protecting data residing across physical, virtual, and cloud environments grow with it. Managing data includes protecting it, indexing and classifying it for true, long-term management, compliance and E-Discovery. Commvault can ensure this with a single pane of glass solution – whether in a private cloud, a Service Provider delivered public cloud or a hybrid cloud environment – across the heterogeneous enter...
DXWorldEXPO LLC announced today that ICC-USA, a computer systems integrator and server manufacturing company focused on developing products and product appliances, will exhibit at the 22nd International CloudEXPO | DXWorldEXPO. DXWordEXPO New York 2018, colocated with CloudEXPO New York 2018 will be held November 11-13, 2018, in New York City. ICC is a computer systems integrator and server manufacturing company focused on developing products and product appliances to meet a wide range of ...