ZerUniverse

How to thoroughly erase a computer

ZerUniverse — Fri, 23 Oct 2015 12:00:00 +0000

Erasing a computer or a hard disk is essential sometimes such as selling your used computer or safely throwing your old hard drives... (Click to read more)

Install dwm - dynamic window manager with Chinese environment

ZerUniverse — Tue, 20 Oct 2015 12:00:00 +0000

DWM is a simple wondow manager. Since I only need terminal and browser in most cases. Dwm would be a better choice for me than Gnome... (Click to read more)

Install Arch Linux on Thinkpad T440 with Windows 10

ZerUniverse — Tue, 20 Oct 2015 11:00:00 +0000

I usually use BIOS for installing Linux system. However, on this T440, a Windows is already installed in UEFI boot mode and I want to keep it. Thus, I decided to try installing Arch on UEFI mode. And actually, it turned out to be easier to use UEFI boot mode... (Click to read more)

Apply a Free SSL Certificate and Make it Work

ZerUniverse — Fri, 22 May 2015 11:00:00 +0000

I Just found that my SSL certificate for this domain expires soon, so I applied a new one from StartSSL today. Currently, StartSSL is the only website offering free SSL certificates which are trusted by most web browsers. It’s not a good idea to sign a self-signed certificate because web browsers will tell your visitors the website they try to visit is dangerous (like the following graph), which is extremely unfriendly... (Click to read more)

Recover Deleted File in Linux

ZerUniverse — Sun, 10 May 2015 11:00:00 +0000

I still clearly remembered once I mistyped mv as rm and I deleted my assignment which takes me an entire weekend to write. That time, I wanted to execute the command: mv xxx.c src/xxx.c (I wanted to put all source code in src folder) but what I really typed in the terminal was: rm xxx.c src/xxx.c. Right after I pressed the enter key, I realized that was a disaster. But it was already too late (though src/xxx.c doesn’t exist, xxx.c will be deleted anyway if that command executes). Fortunately, I recovered it finally but it took much more time than that of recovering a file in Microsoft Windows... (Click to read more)

Add Swap in CentOS

ZerUniverse — Sat, 09 May 2015 11:00:00 +0000

Today when I tried to compile an opensource software in my DigitalOcean VPS, I encountered a weird problem: every time when I make it, the command ends with error message Killed. However, I didn’t press CTRL+C all the time. Then I keyed in command top and I saw gcc used up my memory! So I decided to add a swap file to enlarge my memory... (Click to read more)

Use PDO to Avoid SQL Injection

ZerUniverse — Wed, 06 May 2015 11:00:00 +0000

Ten years ago, people talked about SQL Injection. Today, people still talked about this. The difference is, SQL Injection used to be very easy. For some old website, you might simply input... (Click to read more)

Web Server Security

ZerUniverse — Tue, 05 May 2015 11:00:00 +0000

The security configuration of a web server is very important especially when some confidential data is stored in its database. However, I didn’t do anything to ensure the safety of my server after I installed operating system into it. So I decide to make up this today... (Click to read more)

Start blogging!

ZerUniverse — Tue, 05 May 2015 10:00:00 +0000

I used to think there’s no need for me to write a technical blog. Because everything I need can be found in Internet. However, as time passes by, I found out that techniques/knowledge I use today are supposed to be used in the future (maybe just tomorrow). In this case, I have to search the Internet again since it’s hard for me to remember everything... (Click to read more)