Apply a Free SSL Certificate and Make it Work

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.
>>Read More

Recover Deleted File in Linux

I still clearly remembered once I confused <mv> with <rm> and I deleted my assignment which cost me a whole weekend. 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
>>Read More

Add Swap in CentOS

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!
>>Read More

Web Server Security

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.
>>Read More

Start blogging!

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).
>>Read More