dnstap-ldns software package provides Utility that can decode dnstap encoded files, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install dnstap-ldns
dnstap-ldns is installed in your system.
Make ensure the dnstap-ldns package were installed using the commands given below,
$ sudo dpkg-query -l | grep dnstap-ldns *
You will get with dnstap-ldns package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Network |
| Package | dnstap-ldns |
| Version | 0.2.0-1 |
| Description | Utility that can decode dnstap encoded files |
| Sub Section | Net |