libunbound2 software package provides library implementing DNS resolution and validation, you can install in your Ubuntu 14.04 LTS (Trusty Tahr) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install libunbound2
libunbound2 is installed in your system.
Make ensure the libunbound2 package were installed using the commands given below,
$ sudo dpkg-query -l | grep libunbound2 *
You will get with libunbound2 package name, version, architecture and description in a table
| Distro | Ubuntu 14 04 lts trusty tahr |
| Section | Network |
| Package | libunbound2 |
| Version | 1.4.22-1ubuntu4.14.04.1 [amd64 |
| Description | library implementing DNS resolution and validation |
| Sub Section | Net |