Links: 14 Useful Examples of Linux ‘sort’ Command, 7 Interesting Linux ‘sort’ Command Examples

Sort is a Linux program used for printing lines of input text files and concatenation of all files in sorted order. Sort command takes blank space as field separator and entire Input file as sort key. It is important to notice that sort command don’t actually sort the files but only print the sorted output, until your redirect the output.

This article aims at deep insight of Linux ‘sort‘ command with 14 useful practical examples that will show you how to use sort command in Linux.

Full articles from Tecmint here:
14 Useful Examples of Linux ‘sort’ Command – Part 1
7 Interesting Linux ‘sort’ Command Examples – Part 2

Link: How to use FFMpeg to do simple audio conversion

Here’s a simple FFmpeg how to that will cover just a portion of the framework’s abilities. We will see how you can use the terminal to perform simple conversions of various audio file types including all popular and widely available formats. Using FFmpeg right from the terminal makes it better for performance compared to downloading and installing a GUI tool for FFmpeg, and can also offer more precise settings for the advanced users.

Full article here:
How to use FFMpeg to do simple audio conversion (Howtoforge)
Related: Combine Audio and Video with ffmpeg (David Walsh)

Link: An Introduction To MySQL Database

MySQL is an open source database management software that helps users store, organize, and retrieve data. It is a very powerful program with a lot of flexibility.

This tutorial will explains how to install MySQL, create a sample database, create a table, insert records into the table, and select records from the table.

Full article here:
An Introduction To MySQL Database (Unixmen)

Forum thread: User-specific Caller ID/whitelist/blacklist in Asterisk/FreePBX

Occasionally I see a forum thread that contains enough interesting material that it could be the start of an article, but because it’s stretched through a number of posts, I can only link to the thread. And also, because I’m not the author of any of the original posts, I can’t just copy and paste without possibly violating someone’s copyright. This is one such thread, which discusses the possibility of creating user-specific whitelists or blacklists, or Caller ID name lookup sources in FreePBX or Asterisk. The Caller ID name lookup would be most useful to Google Voice users, since Google Voice doesn’t provide a Caller ID name on incoming calls, just a number. Since there is no way that a user can add or change such listings in the FreePBX interface at present, the trick seems to be to use Google Contacts as the user’s web interface, and then import the data from the user’s Google Contacts list into the Asterisk database at periodic intervals using a cron job.

The interesting thing about this is that it appears that users can have their own individual lists, since each user would apparently have their own Google Contacts, which means that a user could blacklist a caller without blacklisting that caller for all users on the system. It may be a bit tricky to figure out what’s being done from the posts shown, but still it looks like a possibly interesting technique.

Even though FreePBX 12 now offers a contact list in the User Control Panel, there are limitations on how it can be used. What is discussed in this thread apparently does not share those limitations, but does have the limitation that any changes made will not be seen by Asterisk until the next time the Google Contacts database is imported into Asterisk’s database, which is done using some downloadable software, a python script, and a cron job.

Thread here:
User-specific Caller ID/whitelist/blacklist in Asterisk/FreePBX (DSLReports.com)

Link: Create a TimeMachine Backup Storage on the Raspberry Pi

TimeMachine is the way to backup your data on Mac systems. The backup and restore procedure work nicely out of the box with very little hassle involved. I used to backup my data on a local USB disk for some years. However, backups to a USB disk require you to connect the disk, otherwise no backups will be performed.

Apple will sell you the Airport Time Capsulate, which allows for remote backups. But it is also possible to configure your Raspberry Pi to offer remote backup capabilities for the TimeMachine. Turning your Raspberry into a backup target for the TimeMachine is as simple as installing an AFP server on it. In this blog post, I’ll walk through the process of configuring your raspberry to be a remote target for TimeMachine backups.

Full article here:
Create a TimeMachine Backup Storage on the Raspberry Pi (blog.lobraun.de)

Link: Introduction to Samba – Share Files and Directories between Linux, Windows and Mac

Samba is the most popular and efficient way with which you can share your files and directories between Linux, Windows and Mac. You just have to create a Samba user, Decide which file/directory you wish to share and Set the permissions, in order to create a Samba share. Well, initially, this might seem to be difficult- especially for beginners, but when you understand all the configuration options, it will seem to be as simple as anything.

This tutorial will explain how to share files and directories on Linux with Windows and Mac clients.

Full article here:
Introduction to Samba – Share Files and Directories between Linux, Windows and Mac (Your Own Linux..!)

Link: How to access a Linux server behind NAT via reverse SSH tunnel

You are running a Linux server at home, which is behind a NAT router or restrictive firewall. Now you want to SSH to the home server while you are away from home. How would you set that up? SSH port forwarding will certainly be an option. However, port forwarding can become tricky if you are dealing with multiple nested NAT environment. Besides, it can be interfered with under various ISP-specific conditions, such as restrictive ISP firewalls which block forwarded ports, or carrier-grade NAT which shares IPv4 addresses among users.

What is Reverse SSH Tunneling?

One alternative to SSH port forwarding is reverse SSH tunneling. …..

Full article here:
How to access a Linux server behind NAT via reverse SSH tunnel (Xmodulo)

Link: Running Android on Desktop: Which Emulator is the Best?

Android is one of the most popular mobile computing operating systems and powers a diverse range of phones, including the low-end ones and the high-end flagship. The good thing about Android is that other than running it on mobile devices, it can also run on the desktop with a suitable emulator. In case you have an ancient Windows machine and want to convert it into something useful, running Android on it can give your ancient Windows machine a new lease of life.

There are many free Android emulators for Windows on the market but only a few of them could match up to our expectations. Listed below is a carefully curated list of Android emulators for your Windows PC.

Full article here:
Running Android on Desktop: Which Emulator is the Best? (Make Tech Easier)

Link: How to set up NTP server in CentOS

Network Time Protocol (NTP) is used to synchronize system clocks of different hosts over network. All managed hosts can synchronize their time with a designated time server called an NTP server. An NTP server on the other hand synchronizes its own time with any public NTP server, or any server of your choice. The system clocks of all NTP-managed devices are synchronized to the millisecond precision.

In a corporate environment, if they do not want to open up their firewall for NTP traffic, it is necessary to set up in-house NTP server, and let employees use the internal server as opposed to public NTP servers. In this tutorial, we will describe how to configure a CentOS system as an NTP server. Before going into the detail, let’s go over the concept of NTP first.

Full article here:
How to set up NTP server in CentOS (Xmodulo)