The HN.Nguyen Blog

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Building a Secure and Scalable Asset Storage Architecture with AWS S3 and CloudFront

Building a Secure and Scalable Asset Storage Architecture with AWS S3 and CloudFront

Images, documents, avatars, attachments, and other uploaded files are often treated as a secondary concern during the early stages of a project. The application works, users can upload files, and everything seems fine. Until one day the storage structure becomes difficult to maintain, access control becomes inconsistent, CDN integration becomes necessary, or storage costs start growing unexpectedly. A well-designed asset storage architecture prevents many of these problems before they appear. This article covers a practical approach to storing and delivering assets using Amazon S3 and CloudFront while following modern AWS best practices.
Huu Nghia Nguyen Jun 24, 2026
How to Change Your Google Account Email on Mobile

How to Change Your Google Account Email on Mobile

Changing your Google Account email can be done directly from your phone. Follow the steps below to access the email settings and check whether your account supports email changes.
Huu Nghia Nguyen Jun 23, 2026
How to Troubleshoot a Spring Boot Application That Keeps Stopping on an Ubuntu VPS

How to Troubleshoot a Spring Boot Application That Keeps Stopping on an Ubuntu VPS

Keywords: Spring Boot VPS, Ubuntu VPS troubleshooting, Java OOM Killer, Spring Boot memory issue, Nginx 502 Bad Gateway
Huu Nghia Nguyen Jun 10, 2026
How I Fixed a Spring Boot Application That Kept Getting Killed by the Linux OOM Killer

How I Fixed a Spring Boot Application That Kept Getting Killed by the Linux OOM Killer

Recently, my personal blog started going offline several times a day. The application was built with Spring Boot and deployed on a small Ubuntu VPS with 2GB RAM. At first, I thought the problem was related to Java memory settings or PostgreSQL. However, the real reason was different.
Huu Nghia Nguyen Jun 3, 2026
Bangkok Through My Lens — April 2026

Bangkok Through My Lens — April 2026

A collection of moments captured during my trip to Bangkok, Thailand , in April 2026. Shot on a Sony A6400 with a Sigma 18-50mm F2.8 DC DN . No presets. No heavy editing. Only natural light, genuine moments, and the city as I saw it.
Huu Nghia Nguyen May 16, 2026
Memory Tuning for Spring Boot on a 2GB Ubuntu VPS

Memory Tuning for Spring Boot on a 2GB Ubuntu VPS

Running Spring Boot on a small VPS requires careful memory management. After several production incidents, I settled on a simple configuration that works well for my personal blog.
Huu Nghia Nguyen Apr 6, 2026
Why a 2GB VPS Needs Swap Space for Spring Boot Applications

Why a 2GB VPS Needs Swap Space for Spring Boot Applications

Many developers believe that swap should be disabled because it is slower than RAM. While that is technically true, running a small VPS without swap can be dangerous.
Huu Nghia Nguyen Feb 10, 2026
What Is systemd-journald and Should You Limit Its Log Size?

What Is systemd-journald and Should You Limit Its Log Size?

When I was troubleshooting memory issues on my Ubuntu VPS, I noticed something unexpected. One of the largest processes on the server was not Java, PostgreSQL, or Nginx. It was: systemd-journald At first, I thought something was wrong. Why would a logging service use hundreds of megabytes of memory? After spending some time reading the documentation and checking my server, I realized that the behavior was mostly normal. This article explains what systemd-journald does, how it works, and whether you should limit its log usage on a small VPS.
Huu Nghia Nguyen Jan 10, 2026
How I Secured My Ubuntu VPS After Seeing Constant SSH Attack Attempts

How I Secured My Ubuntu VPS After Seeing Constant SSH Attack Attempts

A few weeks after deploying my personal blog to a VPS, I noticed something interesting in the system logs. Every few minutes, new entries appeared: Failed password for root pam_unix(sshd:auth): authentication failure Disconnected from authenticating user root At first, I thought someone was specifically targeting my server. The reality was less dramatic. The internet is constantly scanning public IP addresses looking for weak SSH credentials. If your VPS is exposed to the internet, these attacks will arrive automatically. In this article, I'll share the exact steps I took to harden my Ubuntu VPS without making administration painful.
Huu Nghia Nguyen Jan 9, 2026
Seoul Through My Lens — November 2025

Seoul Through My Lens — November 2025

Seoul is a city where tradition and modern life exist side by side. Ancient palaces stand among glass towers, quiet alleys lead to vibrant neighborhoods, and every season brings a different atmosphere to the streets. This photo journal captures my journey through Seoul in November 2025, during the final weeks of autumn. Every photograph was taken with an iPhone and presented as naturally as possible. No presets. No heavy editing. Only original photos, natural light, and the city as I saw it.
Huu Nghia Nguyen Nov 6, 2025
How to Install Cursor IDE on Ubuntu

How to Install Cursor IDE on Ubuntu

Cursor is a modern AI-powered IDE designed for developers who want to boost productivity. Since Cursor is distributed as an AppImage , it can run on most Linux distributions without complex setup. In this guide, we’ll walk through installing and configuring Cursor IDE on Ubuntu.
Huu Nghia Nguyen Sep 4, 2025
Login to GitHub on macOS Using SSH Key

Login to GitHub on macOS Using SSH Key

This guide will show you how to create an SSH key on your computer and add it to GitHub. By doing this, you can establish a secure and convenient connection between your computer and GitHub, making it easier to clone, pull, and push repositories without having to enter your password every time.
Huu Nghia Nguyen Aug 29, 2025

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