jffs2-modules-3.16.0-4-orion5x software package provides JFFS2 filesystem support, you can install in your Debian 8 (Jessie) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install jffs2-modules-3.16.0-4-orion5x
jffs2-modules-3.16.0-4-orion5x is installed in your system.
Make ensure the jffs2-modules-3.16.0-4-orion5x package were installed using the commands given below,
$ sudo dpkg-query -l | grep jffs2-modules-3.16.0-4-orion5x*
You will get with jffs2-modules-3.16.0-4-orion5x package name, version, architecture and description in a table
| Distro | Debian 8 jessie |
| Section | debian-installer udeb packages |
| Package | jffs2-modules-3.16.0-4-orion5x |
| Version | 3.16.36-1+deb8u1 |
| Description | JFFS2 filesystem support |
| Sub Section | Debian-installer |