From an urgent notice on their web site:
On March 17, 2021, Stratus Technologies, Inc. was the victim of a ransomware event. Upon detecting suspicious activity, we took several systems offline to isolate the issue and began to initiate our business continuity plan. Additionally, we notified federal law enforcement authorities and enlisted third-party subject matter specialists to assess the nature and scope of the event.
As a precautionary measure, we took the Active Service Network (ASN) and Stratus Service Portal off-line. With respect to the ASN, we contacted our customers and partners to provide further support.
Information for customers as to how to obtain support is listed on their site under the notice.
This incident does not appear to be posted on any dedicated leak site at the time of this publication.