9mount software package provides plan9 filesystem (v9fs) user mount utilities, 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 9mount
9mount is installed in your system.
Make ensure the 9mount package were installed using the commands given below,
$ sudo dpkg-query -l | grep 9mount *
You will get with 9mount package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Administration Utilities |
| Package | 9mount |
| Version | 1.3-10 |
| Description | plan9 filesystem (v9fs) user mount utilities |
| Sub Section | admin |