bwbar software package provides generates text and graphical readout of current bandwidth use, 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 bwbar
bwbar is installed in your system.
Make ensure the bwbar package were installed using the commands given below,
$ sudo dpkg-query -l | grep bwbar *
You will get with bwbar package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Network |
| Package | bwbar |
| Version | 1.2.3-2.1+b1 |
| Description | generates text and graphical readout of current bandwidth use |
| Sub Section | Net |