A1 Austria Migrates 21TB Elasticsearch Workload to OpenSearch in a Week

Discover how A1 Group, a leading telecommunications provider, is tackling the challenge of moving over 1,000 on-premises applications to the cloud and advancing its data analytics capabilities. Facing new licensing costs and ongoing complexity of managing Elasticsearch, A1 Austria achieved a seamless transition to OpenSearch by Exoscale, powered by Aiven, in just one week. The large 30-node cluster with 21TB of storage is run by just two A1 Austria engineers, while delivering superior scalability and reduced management overhead. Learn how this success story has catalyzed further cloud adoption across A1 Group.

Cloud transformation in pursuit of peak efficiency and high scalability

A1 Group is one of the largest communications providers in Central and Eastern Europe. It serves millions of customers with a broad portfolio of telecoms, internet and mobile services as well as data, IT and digital services. It generated revenues of EUR 5.3bn in 2023, with daughter company, A1 Austria, responsible for more than 50%.

The European market for telcos and communications service providers (CSPs) is exceptionally competitive due to a combination of structural, regulatory and market dynamics. So for companies with strong growth plans like A1 Group, peak efficiency and high levels of scalability are both essential.

To achieve these goals, A1 Group is undertaking a significant transformation of its underlying IT infrastructure and migrating 1,000+ on-premises applications to the cloud. It has a multi-cloud strategy, leveraging European cloud provider Exoscale as well as a hyperscaler for additional flexibility.

One of the earliest, largest and most business-critical workloads to be migrated to the cloud were the Elasticsearch clusters used predominantly by the telco division at A1 Austria for advanced data analytics.

Cost concerns and management burden with Elasticsearch

Data analytics is crucial for telecommunications companies like A1 Austria, providing valuable insights into network performance, customer behavior and service quality. This reflects a growing global trend, with the telecom analytics market projected to increase from USD 8.1 billion in 2024 to nearly USD 31 billion by 2034, according to Precedence Research.

When the cloud transition began, A1 Austria was running on-premises clusters of Elasticsearch and using Grafana® dashboards to visualize the data and provide insights into the network. But the system was becoming increasingly complex, siloed and inefficient to manage. Different people had their own Elasticsearch instances, putting pressure on internal IT.

The situation became particularly acute when Elasticsearch switched from a free, open-source model to a licensing model, creating significant cost concerns to A1 Austria.

In addition, ‘dashboard fatigue’ had started to set in. “Creating efficient dashboards that truly benefited the business could take weeks,” says Alexander Köstenbaumer, Core Observability Engineer, A1 Austria. “Just because it's a dashboard, it doesn't mean it’s helpful — and we saw growing rates of exhaustion and confusion among our colleagues who were spending too much time trying to understand the information being presented to them.”

Data analytics key to safeguarding customer experience

A1 Austria had also grown steadily as a company, often outpacing its peers. That growth led to increased data load which made data management more challenging. For example, indexing large datasets required significant computational resources.

The system was struggling to deliver what users needed. “Elasticsearch seemed overloaded and the performance was getting worse. Our Grafana displays were often slow to load and data was sometimes missing,” says Christoph Reiss VoLTE and VoWif Acceptance Expert in A1 Austria’s telco team, and a daily user of Elasticsearch. “It was frustrating.”

It was also starting to affect business operations. “Our business needs to see what the customer is experiencing,” says Köstenbaumer. “Without reliable analytics, we risk poor customer service and dissatisfaction, which will ultimately harm the company’s revenues and its reputation. It was something we had to address.”

The performance issues, combined with Elasticsearch's shift away from free open-source licensing to a paid model, signaled the need for a change. A1 Austria needed a cost-effective, highly scalable, cloud-hosted alternative that would alleviate the management burden.

Partnering with European cloud provider Exoscale

At the time, A1 Group was leveraging Exoscale’s IT services, including compute, storage, Kubernetes® and container solutions. As a cloud provider committed to open-source technologies with a fully European footprint, Exoscale was enabling A1 Group’s customers to comply with privacy and data sovereignty requirements. After acquiring Exoscale in 2017, A1 Group used its services both internally across its subsidiaries and externally for customer-facing digital solutions.

For all these reasons, Exoscale emerged as the logical partner for A1 Austria to move away from Elasticsearch. All Exoscale’s database services are delivered exclusively by Aiven, including OpenSearch, MySQL®, PostgreSQL®, Apache Kafka® and Grafana. A1 Austria opted for OpenSearch by Exoscale, a managed open-source Elasticsearch alternative.

“Services from Aiven are a crucial part of our portfolio and have made a notable contribution to our growth — both the amount of data we process and the number of customers we serve. Nearly every new customer we bring onboard uses services from Aiven,” says Beatrix Kemfelja, Head of CoE / Sales for Austria, Exoscale.

“Aiven shares our open-source ethos and helps us maintain our European data sovereignty and compliance, which is essential for many of our customers.”

21TB Elasticsearch workload to OpenSearch in a week

Against the backdrop of A1 Group’s wider cloud transformation, Exoscale and the team at A1 Austria initiated a proof of concept for migrating from Elasticsearch to OpenSearch by Exoscale, powered by Aiven.

“It was exactly what we’d been looking for,” says Köstenbaumer. “The migration was really quick and we didn’t need support from Exoscale because it was so easy. It took just one week to get everything up and running. We spent time on connectivity to the new platform, as well as tweaking certain elements like new index templates and lifecycle policies.”

30-node OpenSearch managed by just two people

A1 Austria now has a highly-scalable central observability infrastructure, based on a 30-node OpenSearch cluster with 21TB of storage — Exoscale’s largest deployment. It is growing at a rate of 10 GB of data per day, or 300 GB of data each month, as data analysis and visualization requirements of the A1 Austria telco team increase. Logstash is in place for data ingestion and Grafana dashboards remain for visualization.

“We'll need to add another cluster soon as we’re nearing capacity,” says Köstenbaumer. “To manage storage costs, we’ve adjusted our data retention policies and increased index rollover frequency. Fortunately, Exoscale cloud’s flexible nature allows us to add a small cluster and scale it as our data volume grows.”

Despite its large size, the OpenSearch cluster is managed by just two people at A1 Austria. “Starting a new OpenSearch cluster takes three minutes. It’s just a few clicks for a working instance without any headaches or any issues,” says Köstenbaumer.

Dashboards in days, not weeks or months

All the logs are consolidated into a central repository, which makes data transfer much more efficient and consistent. Performance has improved, making the Grafana dashboards more stable and responsive. The team has also established comprehensive security measures, such as detailed access policies, to safeguard sensitive information.

“Our centralized system supports the fast creation of dashboards. We can get a first version of a dashboard running in two days rather than the weeks or even months it took before,” says Köstenbaumer. “It definitely improves time to action.”

Network issues proactively fixed, big data queries in half the time

From the perspective of A1 Austria’s end users in the telco team, OpenSearch has become an indispensable tool. More than 100 technical users among the core network team rely on it daily to gain valuable insights, and many more have access.

“With OpenSearch, our data visualization dashboards are running much faster. When we make a big data query, it's at least double the speed,” says Reiss. “It helps us identify network issues and fix them before they become major problems.”

The team has implemented custom alerts to monitor key performance indicators (KPIs) from mobile voice and data core networks, including logins, active users, data usage and call failures. When a failure is detected, the responsible service team is immediately notified to investigate and resolve the issue. This dashboard, as well as others, are used by senior management to get an immediate view of how services are performing.

Freeing resources for innovation

Aiven’s experts handle the upgrades and maintenance of the cluster on behalf of Exoscale, releasing internal resources at A1 Austria to focus on high-value tasks around developing apps and innovating with data.

“Before, we spent a lot of time on tasks that weren’t really helping the business,” says Köstenbaumer. “Now people can work in areas where they can add value, which motivates them and helps the business to move forward.”

“OpenSearch from Exoscale, powered by Aiven, has been transformative. As a result, we’re keen to host more of our data infrastructure in the Exoscale cloud and benefit from Aiven’s proven expertise and reliability,” he says.

A1 Austria plans to move its instance of Grafana to Managed Grafana on Exoscale and is exploring Managed Apache Kafka on Exoscale, both powered by Aiven.

OpenSearch migration creates momentum for cloud transformation

The successful move to OpenSearch, one of the first steps in A1 Group’s broader cloud transition, has set a strong precedent for future migrations. “Exoscale has been an invaluable partner in our cloud journey and in enabling us to serve enterprise customers,” says Momtchil Ivanov, Director IT Services, A1 Group. “The triumph of the transition to OpenSearch has ignited a wave of cloud adoption across other parts of A1 Group.”

Indeed, cloud adoption at A1 Group has since started to accelerate. It is migrating between 10 and 20 applications a month, and that rate is increasing.

“Our ultimate goal is to migrate all A1 Group applications to the cloud, minimizing our on-premises infrastructure," says Ivanov. “Using Exoscale’s cloud platform empowers us to develop and deploy customer-facing services more rapidly, with enhanced transparency and cost control. For example, we can deliver the suite of services from Exoscale, powered by Aiven, directly to our customers. It’s an exciting proposition.”

Elasticsearch is a trademark of Elasticsearch BV, registered in the U.S. and in other countries.

Apache Kafka and Kafka are either registered trademarks or trademarks of the Apache Software Foundation in the United States and/or other countries.

OpenSearch, PostgreSQL, MySQL, Grafana and Kubernetes are trademarks and property of their respective owners.