Docker Compose in Production: What Works and What Quietly Burns You

Running Docker Compose in production is a reasonable choice for a single host, but the defaults were chosen for a laptop. A walk through the failure families that actually bite: the deploy gap, unrotated logs filling the disk, anonymous volumes, published ports that bypass your firewall, secrets in environment variables, and health checks that report without acting.

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You Probably Didn’t Harden That Server: A VPS Setup and Hardening Checklist That Verifies Itself

You set PasswordAuthentication no, restarted SSH, and moved on. Months later the logs show successful password logins, because a vendor drop-in file sorted earlier and won. A VPS setup and hardening checklist where every step comes with the command that proves it worked.

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It Works in My Browser: Debugging TLS Certificate Errors in Chains, SANs and Expiry

Your browser shows a padlock and your partner's API client throws "unable to get local issuer certificate". Both are correct. A practical guide to the four things a TLS client actually checks, and to renewal automation that reaches the running server instead of just the disk.

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Your Deploy Key Is a Root Shell: GitHub Actions VPS Deployment Over SSH, Done Carefully

A deploy key in GitHub secrets is a shell on your production server, handed to a container you don't control, running code from maintainers you've never met. Here's how to build the pipeline so a leaked key isn't worth much: forced commands, scoped sudo, pinned actions and a real approval gate.

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DNS Troubleshooting: How to Find the Real Cause in Minutes, Not Hours

Most "the site is down" tickets are really DNS problems wearing a costume. Here's the practical DNS troubleshooting workflow I use — how to read dig output, follow the delegation chain, decode SERVFAIL and NXDOMAIN, and stop blaming propagation for things that are actually caching, TTL, or DNSSEC failures.

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