New to MongoDB Atlas: Cross-Region Replication, New Instance Sizes

Sahir Azam
October 6, 2017 | Updated: August 16, 2023

Our automated database service, MongoDB Atlas, now serves thousands of customers across a wide range of industries, providing high availability, consistent performance, and simplified operations.

Sega’s Hardlight Studio migrated to Atlas to support real-time data processing requirements in the cloud and improve the user experience for millions of mobile gamers.

MongoDB Atlas ensures high availability with a fault-tolerant and self-healing architecture. Replica set members are distributed across availability zones in a customer’s selected region; should a node fail, the election and failover process happen automatically without intervention. You can also choose from 41 regions across AWS, Azure, GCP, ensuring that your managed databases are in close proximity to your application servers for minimal geographic latency. While these deployment configurations serve a large portion of application requirements, customers have asked for more options and flexibility.

Today we are introducing cross-region replication for MongoDB Atlas. Within a single cloud, you can enable cross-region deployments for even better availability guarantees and improved performance for local reads.

Here’s how it works. When creating or modifying your deployment, you’ll now see a “Enable cross-region configurations options” link, shown below:

Selecting this link will present two non-exclusive options:

You can deploy across multiple regions for better availability guarantees, meaning that replica set members in additional regions will participate in the election and automated failover process should your primary fail. Note that you can also select your preferred region; this is the region where reads and writes will default to assuming that there are no active failure or failover conditions.
You can also deploy read-only replica set members. Read-only replica set members allow you to optimize for local reads (reduce read latency) across different geographic regions using a single MongoDB deployment. As the name suggests, these replica set members will not participate in the election and failover process and can never be elected to a primary replica set member.

Let’s look at a few examples. We’ll assume that your preferred region is us-east-1 in AWS, but not only do you want to withstand a partial region outage (an availability zone goes offline), you also want to withstand an outage of an entire AWS region. Your configuration might look something like what’s shown in the image below, where we’ve distributed our 3-node replica set across 3 regions in AWS. You might also increase the number of nodes in your replica set to 5 and keep 2 in us-east-1, your preferred region, 2 in us-east-2, and 1 in us-west-1. This would increase the likelihood that your primary node stays in your preferred region during a partial region outage. Note that Atlas will tell us the availability guarantees offered by our configuration, highlighted in the green lettering.

In the next example, let’s assume that you’re satisfied with the availability guarantees of having your cluster in the us-east-1 region, but you have a significant user base in the UK and want to provide them with an optimal user experience. You might set up a configuration like what’s shown below, deploying a read-only replica set member in London to serve local reads.

In the configuration shown below, we’ve enabled both options — our cluster is distributed across 3 regions in the US to ensure availability in the unlikely event of an entire regional outage AND we have a read-only replica set member for our user base in London.

Cross-region replication is now available on AWS, Azure and GCP. In addition, you can now have clusters in different regions within the same Project and easily move your deployments between regions while preserving availability.

Managed clusters at the right size (and price) for every project

We’re introducing new M2 and M5 instance sizes, available in select regions across all 3 clouds.

Built on a multi-tenant architecture, these new instance sizes allow you to jumpstart your project or scale beyond the M0 free tier, all for a low, predictable price.

As your storage, performance, or isolation requirements change, you can easily move beyond the initial boundaries and scale up to one of our dedicated cluster sizes.

Cross-region replication is now live in MongoDB Atlas. M2s and M5s are in public preview.

As always, we’d love to hear your feedback at mongodb-atlas@mongodb.com.

Not an Atlas user yet? Get started with a 512MB database for free.

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Investing in CS4All: One Year Later

When a couple of New York City high school teachers partnered with MongoDB to teach computer science, did they succeed? Their curriculum was untested, and they were teaching in difficult districts where most students are from poor and minority families. I talked with these two teachers, Jeremy Mellema and Timothy Chen, back in September , when they had completed a summer fellowship at MongoDB and had just started teaching their curriculum; at the end of the academic year this spring, I visited Jeremy and Tim again to find out the result. Their successes were sparse and partial. They discovered that their students' poor reading skills were a barrier to learning to code, and that teaching new coders how to solve problems is, itself, an unsolved problem. With a coarse unit of iteration—a school semester—it is painfully slow to experiment and find teaching methods that work. But even partial wins make a difference for individual kids, and the support of professional engineers at companies like MongoDB can be a powerful accelerant. What engages students Jeremy's main struggle was to get his students excited about code. He was assigned to teach a computer science class at Bronx Compass High School in the fall, using the curriculum he wrote during his fellowship at MongoDB last summer. In the beginning he spent too much time lecturing. “It felt weird,” he said. “It should be more like, ‘Let’s get down and dirty,’ and not, ‘Let’s have me talk to you.’” Even when his students did get their hands on computers, the first exercises were simply retyping Python scripts from a textbook. The payoff, watching a script run without throwing an exception, was hardly satisfying to them. Things started to click when he introduced Python turtle graphics , which gave the class more obvious evidence of their accomplishments. It also allowed Jeremy better opportunities to motivate and engage his students directly. “Some days I would challenge them to see who could make the craziest drawing,” Jeremy says. He would tell his students, “That’s so cool. I only made a star. You definitely beat me today.” Jeremy teaches both history and computer science, and he finds that some of his lowest-performing history students are his best CS students. “It’s satisfying to see them in their element,” he says. In Jeremy's view a computer science class can touch a student's intellect just as deeply as history. “People are multifaceted. You’re not only who you are when you’re in my history class.” Jeremy's computer science class was cancelled this spring; the students at Bronx Compass High School are behind on history credits and there are only three history teachers on staff. For now, computer science is merely an elective, so Jeremy is back teaching history full-time. “I really miss teaching CS,” he says. If he resumes the course, Jeremy thinks it must be livelier. He is reconsidering his use of the videos from How To Think Like a Computer Scientist, which he studied last summer on the recommendation of his mentor Shannon Bradshaw, MongoDB’s vice president of education. The content helped Jeremy train to teach CS, but when he showed the videos to his kids they were bored. Jeremy hopes to make new videos that will draw them in. His students from the fall semester say he should get their advice. Otherwise, they warned, “you might do something that you think is cool but it’s actually super corny.” A head start Although there is no computer science elective this semester, some students are pursuing the topic in other ways. A young woman from his class in the fall, Tatyana Camacho, now interns for the high school’s IT department. I had quoted her in my previous article, and Jeremy tells me she loved it. She commanded him to show her father in the next parent-teacher conference: “You need to show my dad that I’m one of the advanced students.” Jeremy still runs the afternoon Computer Club. I visited the club to meet a student, Daniel Rodriguez, who was tinkering with an Arduino and a circuit board that the school provided. “I don't have the ability to get this equipment otherwise, in my predicament,” says Daniel. He starts his Arduino projects by copying examples. The wiring is easier than the coding for him, he told me, "especially because I'm not the best speller in the world." Once he has the example working he modifies it to his own taste. Most recently, he wanted to show a message but, with only LEDs, he can’t display much. He researched Morse Code and made a light flash the code for “HELLO”, like any programmer demonstrating a system for the first time. “Most people think that once you plug something in, that’s it, it works,” says Daniel. “But I’m the person that makes the circuit run. I tell people, ‘I made it do that.’ And seeing them fascinated by what I did, it makes me, in turn, fascinated by what I'm doing.” Daniel has to return the Arduino at the end of the year. Next year he’ll go to a trade school for electricians. Working with the Arduino will give him an advantage, he hopes, and it seems plausible to me. As he finishes school and starts work as an electrician the world will be changing around him: smart appliances and programmable components will be everywhere. An electrician who loves to code will have a big head start. Making anything they want Timothy Chen teaches in Hell’s Kitchen, at Urban Assembly Gateway School for Technology. I visited his class in May to see how his students had progressed since I last saw them in September. They were involved in a multi-week project called the AP Create Task, part of a national Advanced Placement exam. “They are allowed to make literally anything they want, in any language,” says Tim. Students submit their code and a one-minute video of the program in action, and they may describe their project either in writing or in audio narration. I was surprised by how 21st Century the test is, and how accommodating it could be to students with a deficit in reading and writing. It must be remarkably difficult, however, to score fairly. The Create Task is many students’ first time scoping and integrating a sizable project, and there were flameouts. One young man tried to make a maze game drawn with ASCII characters; it proved too ambitious and he ran out of time. Tim isn’t supposed to help students define the scope of their projects, but if they announce they’re going to tackle something difficult he will push them to list all the components. In the best case, they realize they don’t know how to do most of the project and choose something simpler. One of Tim’s students, Jahseem Maxwell, was building a Go Fish card game in Python, and she was having trouble integrating the pieces. “It has to be a certain order and it's hard to make that order when you don't know, really, what you’re doing. I’m struggling, putting it all together.” Another student, Cecilia Gonzalez, was writing a Choose Your Own Adventure game. She says the AP Create Task encourages students to work in pairs. “We work sort of together but not exactly.” Each must create at least one significant part of the program independently. Cecilia’s game is based on a monster of urban legend called The Rake, which comes closer when you think about it. The game begins by asking questions such as the player’s name and height. She told me the player’s answers will determine “some things that are going to happen,” but she didn’t give away any spoilers. When Tim began teaching the class in September, he hadn’t written the ending yet, either. His greatest fear was his students would learn the curriculum faster than he could write it. By May it was clear that wasn’t a problem. “Some of the students can’t read very well, and that was a big barrier because all the things I made were text,” he says. “Everything just took longer than expected.” Problem solving How do you teach problem solving? This is Tim’s great unanswered question from the year. Perhaps if high school computer science were taught like math, as a series of small problems with only one right answer each, then how to solve those problems wouldn't be such a mystery. But high school CS is taught like art class. Tim’s students invent new projects and somehow solve the unpredictable problems that arise in them. Tim speculates that he would learn problem solving himself by watching an experienced programmer solve a new problem, hit roadblocks, and overcome them. Indeed, that is how I have taught problem solving to MongoDB interns. Together, we attack problems without knowing the answers beforehand. It requires an entire summer of one-on-one collaboration. “I don't think that model works very with the kids,” says Tim, “especially if they are not very good with sitting still for an extended period. I'm not sure how to reach them.” Falling in love Tim, like Jeremy, wants to make more multimedia to reach students despite their poor reading skills. “I want to rethink how it should be done before I start this time. I kind of jumped into it too quickly.” Tim’s main goal is to give kids the chance to fall in love with programming and continue on their own. Many other goals are still out of reach: students at his school score low on the AP test, and few of them are likely to get a college degree in CS or be professional coders. Still, Tim hopes that a more varied course, with audio and video, could bring students farther. “The big hurdle for everyone is teaching problem solving. If I can get that, everything else is easy. I'm still trying to figure out how to do that.”

October 3, 2017

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MongoDB’s 2024 Year in Review

It’s hard to believe that another year is almost over! 2024 was a transformative year for MongoDB, and it was marked by both innovation and releases that further our commitment to empowering customers, developers, and partners worldwide. So without further ado, let’s dive into MongoDB’s 2024 highlights. We’ll also share our executive team’s predictions of what 2025 might have in store. A look back at 2024 MongoDB 8.0: The most performant version of MongoDB ever In October we released MongoDB 8.0 , the fastest, most resilient, secure, and reliable version of MongoDB yet. Architectural optimizations in MongoDB 8.0 have significantly improved the database’s performance, with 36% faster reads and 59% higher throughput for updates. Our new architecture also makes horizontal scaling cheaper and faster. Finally, working with encrypted data is easier than ever, thanks to the addition of range queries in Queryable Encryption (which allows customers to encrypt, store, and perform queries directly on data). Whether you’re a startup building your first app, or you’re a global enterprise managing mission-critical workloads, MongoDB 8.0 offers unmatched power and flexibility, solidifying MongoDB’s place as the world’s most popular document database. Learn more about what makes 8.0 the best version of MongoDB ever on the MongoDB 8.0 page . Delivering customer value with the MongoDB AI Applications Program AI applications have become a cornerstone of modern software, and MongoDB is committed to equipping customers with the technology, tools, and support they need to succeed on their AI journey. That’s why we launched the MongoDB AI Applications Program (MAAP) in 2024, a comprehensive program designed to accelerate the development of AI applications. By offering customers resources like access to AI specialists, an ecosystem of leading AI and tech companies, and AI architectural best practices supported by integrated services, MAAP helps solve customers’ most pressing business challenges, unlocks competitive advantages, and accelerates time to value for AI investments. Overall, MAAP’s aim is to set customers on the path to AI success. Visit the MongoDB AI Applications Program page or watch our session from AWS re:Invent to learn more! Advancing AI with MongoDB Atlas Vector Search In 2024, MongoDB further cemented its role in the AI space with enhancements to MongoDB Atlas Vector Search . Recognized in 2024 (for the second consecutive year!) as one of the most loved vector databases , MongoDB continues to provide a scalable, unified, and secure platform for building cutting-edge AI use cases. Recent advancements like vector quantization in Atlas Vector Search help deliver even more value to our customers, enabling them to scale applications to billions of vectors at a lower cost. Head over to our Atlas Vector Search quick start guide to get started with Atlas Vector Search today, or visit our AI resources hub to learn more about how MongoDB can power AI applications. Search Nodes: Performance at scale Search functionality is indispensable in modern applications, and with Atlas Search Nodes, organizations can now optimize their search workloads like never before. By providing dedicated infrastructure for Atlas Search and Vector Search workloads, Search Nodes ensure high performance (e.g., a 40–60% decrease in query times), scalability, and reliability, even for the most demanding use cases. As of this year , Search Nodes are generally available across AWS, Google Cloud, and Microsoft Azure. This milestone underscores MongoDB’s commitment to delivering powerful solutions that scale alongside our customers’ needs. To learn more about Search Nodes, check out our documentation or watch our tutorial . Looking ahead: MongoDB’s 2025 predictions After the excitement of the past few years, 2025 will be defined by ensuring that technology investments deliver tangible value. Organizations remain excited about the potential AI and emerging technologies hold to solve real business challenges, but are increasingly focused on maintaining a return on investment. “Enterprises need to innovate faster than ever, but speed is no longer the only measure of success. Increasingly, organizations are laser-focused on ensuring that their technology investments directly address critical business challenges and provide clear ROI and competitive advantage—whether it’s optimizing supply chains, delivering hyper-personalized customer experiences, or scaling operations efficiently,” said Sahir Azam, Chief Product Officer at MongoDB. “In 2025, I expect to see organizations make significant strides in driving this innovation and efficiency by applying AI to more production use cases and by maturing the way they leverage their data to build compelling and differentiated customer experiences.” Indeed, we expect to see organizations make more strategic investments in emerging technologies like gen AI—innovating with a sharp focus on solving business challenges. “In 2025, we can expect the focus to shift from ‘what AI can do’ to ‘what AI should do,’ moving beyond the hype to a clearer understanding of where AI can provide real value and where human judgment is still irreplaceable,” said Tara Hernandez, VP of Developer Productivity at MongoDB. “As we advance, I think we’ll see organizations begin to adopt more selective, careful applications of AI, particularly in areas where stakes are high, such as healthcare, finance, and public safety. A refined approach to AI development will be essential—not only for producing quality results but also to build trust, ensuring these tools genuinely support human goals rather than undermining them.” With more capable, accessible application development tools and customer-focused programs like MAAP at developers’ fingertips, 2025 is an opportunity to make a data-driven impact faster than ever before. "Right now, organizations have an opportunity to leverage their data to reimagine how they do business, to more effectively adapt to a changing world, and to revolutionize our quality of life,” said Andrew Davidson, SVP of Products at MongoDB. “By harnessing our latest technologies, developers can build a foundation for a transformative future." Head over to our updates page to learn more about the new releases and updates from MongoDB in 2024. Keep an eye on our events page to learn what's to come from MongoDB in 2025!

December 19, 2024