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Case studies

Real cases, anonymised. Customer names, hostnames and third-party module names have been changed. The kernel output and the crash sessions are as they were.

  • Database host panicking during the nightly backup window

    A financial services customer ran a PostgreSQL primary on RHEL 9.4. Roughly every two to three days the host panicked between 02:00 and 03:00 and rebooted, dropping replication and triggering a failover. The crashes had been going on for five weeks.

    Root cause. The snapshot driver, version 4.2.1, in its session release path. The OS kernel and the EDR sensor were ruled out with evidence from every CPU's stack.

    • RHEL 9.4
    • list_del corruption
    • Snapshot driver
    • Use-after-free