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Ubuntu

By Greg Nowak, 24 August, 2021

How to Flush the DNS Cache on Ubuntu Linux

Flush Ubuntu’s DNS cache safely, identify the resolver actually in use, and verify website, email, or API cutovers without guessing.

Install a Specific MySQL Version on Ubuntu Without Creating Upgrade Debt

Choose a supported MySQL release on Ubuntu, install it through Oracle’s APT repository, and handle exact-version pinning without creating hidden upgrade debt.

Fix mailR and rJava Errors on Ubuntu Servers

A production-aware guide to fixing mailR and rJava failures on Ubuntu, from libjvm.so and javareconf to reliable scheduled-job tests.

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