Sustained high node CPU

Cases

1. IL-0100 PostHog's feature flags pods were packed onto Kubernetes nodes that were too small for their CPU requests, and CPU saturation above 90% caused three outages in ten days through Redis overload, connection pool exhaustion and slow queriesPostHog · 2025

   Root cause Capacity exhaustion

2. IL-0087 After a cold reboot of RKE2 nodes, pods could not get IP addresses because Multus could not reach the Kubernetes API, and further reboots spread the failure to every nodeFyra Labs · 2023

   Root cause Not stated

3. IL-0094 Student pods filled the shared nodes of a JupyterHub cluster and starved the hub's core pods, freezing the hub2i2c · 2020

   Root cause Capacity exhaustion

4. IL-0052 A cryptocurrency miner ran on every node of the development and staging clusters through a public, unauthenticated Weave Scope dashboardJW Player · 2019

   Root cause Configuration change

5. IL-0064 CPU-heavy pods packed onto one Google Cloud node drove it to kernel panics, and the crash moved from node to node until the site was downMoonlight · 2019

   Root cause Capacity exhaustion