HOW TO: Enable rng-tools on Ubuntu VPS Server 16.04 for more "random" data

Introduction and Summary:

Headless VPS servers can suffer from a lack of random data inputs since there is little if any hardware to pull truly random data from (mouse, keyboard, webcams, entropy keys, etc.).  A hack for semi-random data to be generated in software is possible with rng-tools.  These instructions will help you install rng-tools on your VPS and hack the config to pull from the urandom file.

Note: This random data is not truly random and it is generally not considered secure for highly sensitive applications.  I'll be using it for generating obfuscation data, so true randomness is not important to me. Also, my paranoia level is in the mid to low range - if you're requiring higher security solutions, please skip this article.

Prerequisites:

• Linux Ubuntu 16.04 LTS Server
• Console Access
• Root level permissions

Instructions:

1. Connect to the server console (local or SSH)
2. Install the rng-tools package:

  sudo apt update && apt install rng-tools

Note: If you start the service, you will see that it fails:

systemctl status rng-tools
● rng-tools.service
   Loaded: loaded (/etc/init.d/rng-tools; bad; vendor preset: enabled)
   Active: failed (Result: exit-code) since Thu 2017-10-26 04:11:02 EDT; 36min ago
     Docs: man:systemd-sysv-generator(8)
  Process: 299 ExecStart=/etc/init.d/rng-tools start (code=exited, status=1/FAILURE)
Oct 26 04:11:02 ubuntuvps systemd[1]: Starting rng-tools.service...
Oct 26 04:11:02 ubuntuvps rng-tools[299]: Starting Hardware RNG entropy gatherer daemon: (Hardware RNG device inode not found)
Oct 26 04:11:02 ubuntuvps rng-tools[299]: /etc/init.d/rng-tools: Cannot find a hardware RNG device to use.
Oct 26 04:11:02 ubuntuvps systemd[1]: rng-tools.service: Control process exited, code=exited status=1
Oct 26 04:11:02 ubuntuvps systemd[1]: Failed to start rng-tools.service.
Oct 26 04:11:02 ubuntuvps systemd[1]: rng-tools.service: Unit entered failed state.
Oct 26 04:11:02 ubuntuvps systemd[1]: rng-tools.service: Failed with result 'exit-code'.

3. Add the /dev/urandom path to the rng config file:

  sudo echo "HRNGDEVICE=/dev/urandom" >> /etc/default/rng-tools

4. Start the service again

  systemctl start rng-tools

5. Check the status of rng-tools

  systemctl status rng-tools

● rng-tools.service
   Loaded: loaded (/etc/init.d/rng-tools; bad; vendor preset: enabled)
   Active: active (exited) since Thu 2017-10-26 04:47:45 EDT; 2s ago
     Docs: man:systemd-sysv-generator(8)
  Process: 562 ExecStart=/etc/init.d/rng-tools start (code=exited, status=0/SUCCESS)
Oct 26 04:47:45 ubuntuvps systemd[1]: Starting rng-tools.service...
Oct 26 04:47:45 ubuntuvps rng-tools[562]: Starting Hardware RNG entropy gatherer daemon: rngd.
Oct 26 04:47:45 ubuntuvps systemd[1]: Started rng-tools.service.
Oct 26 04:47:45 ubuntuvps rngd[564]: RNDADDENTROPY failed: Operation not permitted

Blog Formatting Guide:

• Commands written in Consolas in BLUE are LOCAL Client Shell Commands (I'm running an Ubuntu local client)
• Commands written in Consolas in RED are REMOTE Server Shell Commands (usually in SSH)
• All commands in Courier and BOLD are CUSTOM user variables that your should change for your configuration.
• All text written in Courier and PURPLE are file contents as shown in a text editor.

Helpful References:

Jon Stephen's post. Thank's Jon!