ipv6calc software package provides small utility for manipulating IPv6 addresses, 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 ipv6calc
ipv6calc is installed in your system.
Make ensure the ipv6calc package were installed using the commands given below,
$ sudo dpkg-query -l | grep ipv6calc *
You will get with ipv6calc package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Network |
| Package | ipv6calc |
| Version | 0.99.1-1 |
| Description | small utility for manipulating IPv6 addresses |
| Sub Section | Net |