Day 27: Git Revert vs Reset and Making an AWS VPC Subnet Public

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A DevOps learning exercise on Day 27 tackled two deceptively simple-sounding tasks: undoing a pushed Git commit and making an AWS VPC subnet publicly accessible. Git's revert command safely undoes a pushed commit by adding a new inverse commit to the history, while reset rewrites history and should never be used on already-pushed commits shared with others. On the AWS side, a 'public subnet' is not a built-in toggle but requires four distinct steps: creating an Internet Gateway, attaching it to the VPC, adding a default route in a route table, and associating that route table with the subnet. Missing any single step produces no error message — just silent connectivity failure, making it particularly difficult to debug. Both tasks illustrate how operations that appear to be a single action are in fact multi-step processes with meaningful consequences if done incorrectly.

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