ClearSky Data

About ClearSky Data

ClearSky Data, founded in Boston in 2014 by Ellen Rubin and Lazarus Vekiarides, offered a cloud-based enterprise storage management solution before being acquired by Amazon Web Services (AWS) in 2019. The company secured $59.4 million in funding over three rounds from investors including Highland Capital Partners, General Catalyst, and Polaris Partners. The founders brought extensive experience in enterprise infrastructure to the venture. Ellen Rubin, a serial entrepreneur with a Harvard MBA, previously co-founded CloudSwitch, a cloud enablement software company acquired by Verizon, and was an executive at Netezza, which had a successful IPO. Lazarus Vekiarides, the CTO, also had a background in developing storage solutions.

The company's primary business was providing a fully managed service for enterprise storage, data protection, and disaster recovery. This service targeted enterprise IT departments, aiming to simplify their data lifecycle and reduce infrastructure costs. The business model was a subscription-based, pay-as-you-go service, making it an agile solution for clients. By combining the performance of local storage with the scalability and economics of the cloud, ClearSky Data addressed key market concerns about latency and performance in cloud adoption.

ClearSky Data's service was built on a unique architecture that utilized a tiered caching system. An on-premises appliance, the ClearSky Edge, used SSDs to cache hot, frequently accessed data for high performance, supporting iSCSI, Fibre Channel, and later, NAS protocols (NFS and SMB). Warm data was kept at metropolitan point-of-presence (PoP) data centers, often in partnership with providers like Equinix and Digital Realty, ensuring low latency. Cold, less frequently accessed data was tiered to public cloud object storage, such as Amazon S3. This model provided a single, durable copy of data that was accessible from multiple locations, eliminating the need for separate primary, backup, and disaster recovery storage infrastructure. The entire service was managed through a web-based GUI, simplifying deployment and data visualization for clients. Following its acquisition, the company's operations were integrated into AWS, and its website was taken offline.