RivasSec

Infrastructure. Security. Insight.

Field notes on infrastructure security, cloud hardening, Kubernetes, IAM, and OSINT by RivasSec.

Taming the OOM Killer: Process Priorities on Linux

Posted on Fri 18 April 2025 in DevSecOps • 3 min read

linux
oom-killer
sysadmin
hardening
devsecops

The Linux OOM Killer decides what dies under memory pressure. Protect sshd, mysqld, and other critical processes with oom_score_adj via a small script.

The 208.5-Day Kernel Bug: Uptime, Overflow, and Risk

Posted on Wed 16 April 2025 in DevSecOps • 2 min read

kernel
linux
bug
devsecops

A 2012 Linux kernel bug caused CPU lockups after 208.5 days of uptime due to an integer overflow in sched_clock(). RHEL 5/6 lesson: patch and observe uptime.

The 2012 Leap Second: When Time Broke Java and the Cloud

Posted on Tue 15 April 2025 in Incident Retrospectives • 3 min read

kernel
linux
java
ntp
sre

The 2012 leap second broke Reddit, Yelp, Java apps, and more. A retrospective on how fragile timekeeping bit the cloud, and what SRE teams should do today.