Category: Linux

Simplest guide to config tomcat to use https with lets encrypt’s free cert

Support you have generate a standalone cert using certbot command, and your cert is in /etc/letsencrypt/live/ . If not, follow this https://www.digitalocean.com/community/tutorials/how-to-use-certbot-standalone-mode-to-retrieve-let-s-encrypt-ssl-certificates-on-ubuntu-16-04 Execute openssl command and remember your password Edit tomcat’s conf/server.xml, you just need one connector to serve 8443, no need other conntector Restart your tomcat, it is done. Below is the virtualhost to […]

Godaddy cheap VPS之經驗

係Godaddy起左隻最Cheap VPS, $160蚊個月, 得一粒vcore同1GB Ram, 行ubuntu + mysql + apache + wordpress. 正常黎講要兩三個星期restart一次mysql因為out of memory. 行wordpres兩年之後response time趑黎越慢, 有成十秒先load到個page. 裝左W3 Total Cache之後快左好多, 一兩秒就load到, 建議大家一定要裝.

Analyst android ELF dependency-graph by elf-dependency-walker

Someone asked me in email about using elf-dependency-walker to analyst library or executable in linux. I found out android is using ELF format for its libraries or executables too. So the rest is simple. Please download the android emulator, within the directory there is the system image, which contain the file system. You can see in […]

solved : compile error in ffmpeg “error: invalid combination of opcode and operands”‏

I am using ubuntu 12.04 64 bits and trying compile ffmpeg and got this error: libavfilter/x86/vf_pullup.asm:59: error: invalid combination of opcode and operands libavfilter/x86/vf_pullup.asm:138: error: invalid combination of opcode and operands libavfilter/x86/vf_pullup.asm:175: error: invalid combination of opcode and operands To solve this, add “–disable-mmx” to your ./configure

sox and ffmpeg (convert hls into live hls) usage

These are the basic usage of SOX This script will convert ffmpeg HLS into “live streaming HLS” The above script has to run with ffmpeg: /root/download/ffmpeg-2.1.4/ffmpeg -f alsa -ac 2 -i hw:0,0 -strict experimental -acodec libmp3lame -map 0 -f segment -segment_list out.m3u8 -segment_format libmp3lame -segment_time 0.5 -segment_list_flags +live ‘a%05d.mp3’

How to change Fedora’s font rendering to get an Ubuntu-like result

Font rendering is a matter of taste. However, I personally think Ubuntu’s default font rendering is the most eye-pleasing one of the whole Linux eco-system. And if a website’s CSS font stack is looking good on Ubuntu, you can be relatively sure that it also works for Mac or MS Windows as long as the used fonts are available on these […]