DevOps Day 4: Linux File Permissions and S3 Versioning as Error-Recovery Essentials

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A DevOps practitioner on Day 4 of a 100-day learning challenge focused on two foundational safeguards: Linux file permissions and AWS S3 versioning. Using chmod 755, they configured scripts so only the owner can modify them while others retain read and execute access, applying the principle of least privilege to reduce accidental changes in production. On the cloud storage side, S3 versioning was enabled via the AWS CLI to ensure deleted or overwritten objects can be recovered rather than permanently lost. Though the two tasks appear unrelated, both address the same underlying risk — human error — by either restricting who can alter files or preserving a path back when the wrong change is made. The session underscores that resilient systems depend less on preventing every mistake and more on limiting the damage when mistakes inevitably occur.

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