Source URL: https://simonwillison.net/2024/Dec/13/openai-postmortem/#atom-everything
Source: Simon Willison’s Weblog
Title: OpenAI’s postmortem for API, ChatGPT & Sora Facing Issues
Feedly Summary: OpenAI’s postmortem for API, ChatGPT & Sora Facing Issues
OpenAI had an outage across basically everything for four hours on Wednesday. They’ve now published a detailed postmortem which includes some fascinating technical details about their “hundreds of Kubernetes clusters globally".
The culprit was a newly deployed telemetry system:
Telemetry services have a very wide footprint, so this new service’s configuration unintentionally caused every node in each cluster to execute resource-intensive Kubernetes API operations whose cost scaled with the size of the cluster. With thousands of nodes performing these operations simultaneously, the Kubernetes API servers became overwhelmed, taking down the Kubernetes control plane in most of our large clusters. […]
The Kubernetes data plane can operate largely independently of the control plane, but DNS relies on the control plane – services don’t know how to contact one another without the Kubernetes control plane. […]
DNS caching mitigated the impact temporarily by providing stale but functional DNS records. However, as cached records expired over the following 20 minutes, services began failing due to their reliance on real-time DNS resolution.
It’s always DNS.
Via @therealadamg
Tags: devops, dns, kubernetes, openai, chatgpt, postmortem
AI Summary and Description: Yes
Summary: OpenAI’s postmortem reflects on a significant outage caused by a newly deployed telemetry system that strained Kubernetes API operations. This incident underscores the importance of effective monitoring configurations in cloud infrastructure and the critical role of DNS in service reliability.
Detailed Description: OpenAI experienced a four-hour outage affecting multiple services, including API and ChatGPT, due to a misconfigured telemetry system. This postmortem provides important technical insights that can be valuable for professionals engaged in infrastructure security, cloud computing, and DevSecOps.
– **Telemetry System Issues**:
– The newly deployed telemetry service had a broad operational impact, leading to unexpected resource demands on Kubernetes clusters.
– The configuration issues caused excessive Kubernetes API operations across thousands of nodes, overwhelming the API servers.
– **Kubernetes Control Plane Failure**:
– The Kubernetes control plane, essential for managing services and the communication among them, became strained under the load, leading to downtime.
– This illustrates a potential vulnerability in cloud infrastructure when scaling out telemetry or monitoring systems.
– **Impact on DNS Services**:
– The incident highlights the interdependence of DNS services on the Kubernetes control plane for service discovery.
– Although DNS caching temporarily alleviated the problem by serving stale records, the expiration of these caches resulted in service failures.
– **Key Takeaways for Professionals**:
– The postmortem reiterates the need for careful configuration management when deploying new monitoring systems in production environments.
– Understanding the implications of DNS in cloud environments is crucial for maintaining service reliability and avoiding outages.
– This case serves as a reminder of the complexity of cloud infrastructures and the cascading effects of single points of failure.
Overall, the significance of this incident lies in its technical insights, which are critical for infrastucture security and compliance professionals, emphasizing the importance of monitoring and dependency management in complex cloud architectures.