Linux on Junian Dev

How to Allow Underscore Headers in Nginx

author@junian.dev (Junian Triajianto) — Sun, 28 Sep 2025 02:43:24 +0700

Have you ever noticed that some HTTP request headers are missing when using Nginx?

I experienced this issue myself. Headers containing underscores (such as _Security_Token_ or _Device_ID_) were silently dropped by Nginx. This caused problems during mobile app testing, as token authentication kept failing.

It turns out that HTTP headers with underscores are uncommon and generally discouraged when possible.

The problem is, sometimes you don’t have control over how the upstream server works.

How I Accidentally Discovered Crypto-Miner Malware (perfctl) on an Ubuntu Server

author@junian.dev (Junian Triajianto) — Fri, 03 Jan 2025 13:12:21 +0700

It all started with an Upwork job described as follows:

Help Installing MongoDB CE 8 on Ubuntu 24.04 LTS

I followed the instructions here:
https://www.mongodb.com/docs/manual/tutorial/install-mongodb-on-ubuntu/
But obviously, I’m missing something. Any help would be greatly appreciated.

Upwork Job Post

I submitted my proposal, thinking it would be a straightforward task—just follow the MongoDB installation guide, and it’d be done in minutes.

How to Run Microsoft Edge without CORS Restriction

author@junian.dev (Junian Triajianto) — Fri, 25 Oct 2024 12:59:57 +0700

As a web developer, you likely need to test your REST API locally. When using a browser like Microsoft Edge, you might encounter issues such as the following message.

Access to fetch at ‘http://localhost:8000/api’ from origin ‘http://localhost:3000’ has been blocked by CORS policy: No ‘Access-Control-Allow-Origin’ header is present on the requested resource. If an opaque response serves your needs, set the request’s mode to ’no-cors’ to fetch the resource with CORS disabled.

How to Run Google Chrome without CORS Restriction

author@junian.dev (Junian Triajianto) — Mon, 07 Oct 2024 10:02:06 +0700

If you’re a Web developer you probably have a task to test your REST API locally. When you’re using a browser like Google Chrome, you may experience some issues like the following message.

Access to fetch at ‘http://localhost:8080/api’ from origin ‘http://localhost:8000’ has been blocked by CORS policy: No ‘Access-Control-Allow-Origin’ header is present on the requested resource. If an opaque response serves your needs, set the request’s mode to ’no-cors’ to fetch the resource with CORS disabled.

Disable Mail Notification from Cron

author@junian.dev (Junian Triajianto) — Thu, 14 Jan 2021 11:50:06 +0700

Have you ever use your Raspberry Pi terminal session and you see following message randomly?

You have new mail in /var/mail/pi

Maybe you’re wondering who’s sending these emails. To know that, you can type mail to check your inbox. If you see several messages like following line, then it’s caused by cron job.

$ mail
"/var/mail/pi": 2047 messages 2047 new
>N   1 Cron Daemon        Wed Jan 13 18:50  22/681   Cron <pi@retropie> /home/pi/go/bin/gonetweet
 N   2 Cron Daemon        Wed Jan 13 18:51  21/3540  Cron <pi@retropie> /home/pi/autotweet.sh
 N   3 Cron Daemon        Wed Jan 13 18:51  22/681   Cron <pi@retropie> /home/pi/go/bin/gonetweet
 N   4 Cron Daemon        Wed Jan 13 18:52  22/681   Cron <pi@retropie> /home/pi/go/bin/gonetweet
 N   5 Cron Daemon        Wed Jan 13 18:52  21/3540  Cron <pi@retropie> /home/pi/autotweet.sh

To stop cron sending you emails, you can just add >/dev/null 2>&1 to the end of your cron job.

CMake Version 3 Installation on Ubuntu 14.04

author@junian.dev (Junian Triajianto) — Sat, 04 Aug 2018 10:25:08 +0700

Recently I’ve been trying to do research on OpenAirInterface using a LimeSDR. Since I’m using their master branch source code, I have to use the old Ubuntu 14.04. For some reasons, I need to test it using the latest LimeSuite source code and compile it myself.

One thing I realized when I did building process for LimeSuite, it throws an error saying that the installed cmake version in the system doesn’t meet the requirements. It needs cmake version 3, but mine was version 2.