21st June 2019

ZRH1 - Flow App Engine Unexpected restart of two hardware nodes

Two of the Hardware-Nodes within the Flow App Engine Cluster in ZRH1 run in an unexpected restart. As a result, all affected containers have been automatically restarted. Apologies for the inconvenience and thank you for your patience, while we investigate the root-cause.

Update: The root-cause analysis showed that the Linux kernel version of the affected servers ran into a bug in combination with the kernel live patching functionality. On the positive side, the unexpected reboot has brought in the latest kernel where this bug has been fixed.