June 08, 2026
Explained: RAS on z/OS
A memory chip fails inside a running mainframe. In a typical server, this would be a crash: a blue screen, a kernel panic, an outage. On an IBM Z system, the error is detected, the affected memory is reconstructed from redundant data held elsewhere in the memory subsystem, and the repair is logged. The running workload continues without interruption. No operator is notified. No ticket is opened. The system fixed itself. This is not exceptional be… Read More
by Phee Jay