Tip

I had quite simple task - compare two lists of hosts and check if hosts from first one are also on the second one. I started with diff: diff -u biglist.txt hosts_to_check.txt | grep -E "^\+" It was fine but output needs some filtering to get what I want. I’ve found another example with grep: grep -Fxv -f biglist.txt hosts_to_check.txt | sort -n This will search for all lines in hosts_to_check.txt which don’t match any line in biglist.txt. So after this I’ve got list of hosts that I have to check. That’s exactly what I need 😄

Learn how to change the default WSUS port from 8530 to 80 on Windows Server 2012, ensuring compatibility with older configurations and resolving IPv6-only issues.

Few days ago I’ve read a book ‘Even Faster Web Sites‘ about websites optimisation and I found one thing usefuluseful, not only on websites. There was a small tip about looploop unlooping. I want to quote them for later use. First - with switch statement var iterations = Math.ceil(values.length / 8); var startAt = values.length % 8; var i = 0; do { switch(startAt) { case 0: process(values[i++]); case 7: process(values[i++]); case 6: process(values[i++]); case 5: process(values[i++]); case 4: process(values[i++]); case 3: process(values[i++]); case 2: process(values[i++]); case 1: process(values[i++]); } startAt = 0; } while(--iterations > 0); Second - without switch var iterations = Math.floor(values.length / 8); var leftover = values.length % 8; var i = 0; if(leftover > 0) { do { process(values[i++]); } while(--leftover > 0); } do { process(values[i++]); process(values[i++]); process(values[i++]); process(values[i++]); process(values[i++]); process(values[i++]); process(values[i++]); process(values[i++]); } while (--iterations > 0); I found second example more readable and I prefer it. These examples after translation could be easily used in other scripting languages.

Some time ago I’ve show how to precompress js and css file with gzip to be available for Nginx’s mod_gzip. In default configuration Apache don’t have such module but similar functionality could be achieved with few custom rewirtes. Basically we will start with these rewrites to serve gzipped CSS/JS files if they exist and the client accepts gzip compression: RewriteEngine on RewriteCond %{HTTP:Accept-encoding} gzip RewriteCond %{REQUEST_FILENAME}\.gz -s RewriteRule ^(.*)\.(js|css)$ $1\.$2\.gz [QSA] Then we need to setup proper content types for such compressed files - I know how to do this in two ways: ...

I’m happy owner of Galaxy Nexus 7 and lately I updated my tablet to Android 4.4 Kitkat. One of features I most expected was ability to block some permissions of some applications. Such setting was available in 4.4 version but was removed in latest 4.4.2 - Google didn’t explain it exactly why. I don’t like when for ex. game need: camera or GPS access - for what I asked? But there is new app so called App Ops that unhides build-in interface allowing edit of application permissions. I strongly suggest to install it. ...

Lately I tried to remove some streams from MKV file - I wanted: video, audio in my language and no subtitles. I achieved it with mkvtoolnix utils. Firstly I have to identify streams in file: $ mkvmerge -i input_file.mkv File 'test.mkv': container: Matroska Track ID 0: video (V_MPEG4/ISO/AVC) Track ID 1: audio (A_DTS) Track ID 2: audio (A_AC3) Track ID 3: audio (A_DTS) Track ID 4: audio (A_AC3) Track ID 5: subtitles (S_TEXT/UTF8) Track ID 6: subtitles (S_TEXT/UTF8) Chapters: 16 entries You could use more verbose tool mkvinfo for that purpose too. ...

Some time ago I prepared a PC that was responsible for batch encoding of movies to formats suitable for web players (such as. Video.js  external link , JW Player  external link , Flowplayer  external link , etc.) ...

I was configuring GlusterFS on few servers using Ansible  external link and have a need to update /etc/hosts with hostnames for easier configuration. I found this one working: - name: Update /etc/hosts lineinfile: dest=/etc/hosts regexp='.*{{item}}$' line='{{hostvars.{{item}}.ansible_default_ipv4.address}} {{item}}' state=present with_items: '{{groups.somegroup}}' Source: http://xmeblog.blogspot.com/2013/06/ansible-dynamicaly-update-etchosts.html  external link

Learn how to reset a user password in your own Ghost Blog by accessing the SQLite database and updating the password hash.

Learn about inodes exhaustion on XFS, how to check inode limits, and how to adjust the inode percentage to prevent issues on your Linux filesystem.