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  • cached-imds-client: cache static IMDS responses to improve robustness

    calendar Feb 15, 2026 · 1 min read · AWS Go  ·
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    I recently encountered IMDS (Instance Metadata Service) request failures with this error: 1"caller": "actor/actor.go:101", 2"error": "operation error ec2imds: GetMetadata, failed to get rate limit token, retry quota exceeded, x available, y requested The root cause: the aws-sdk-go-v2 IMDS …


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  • Mysterious Image Pull Failures: "401 Unauthorized" and "Not Found" After Migrating Containerd to v2

    calendar Oct 12, 2025 · 7 min read · container AWS  ·
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    Early this year, we migrated containerd from v1.7 to v2.0.5. However, we quickly noticed image pulls from Amazon Elastic Container Registry (ECR) began failing for both public and private ECR repositories. For example: 1# public ECR 2FATA[0031] failed to resolve reference …


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Peng Zhang

Software Engineer

Recent Posts

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  • cached-imds-client: cache static IMDS responses to improve robustness
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  • Be careful making thread-aware syscalls in Go: lock the thread

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Peng Zhang

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