we have fortiweb 100E, it has an issue related to its database status and fortiweb dashboard always shows it is not available and we show issue db rebuild command at the same time the fortiweb itself works well, so we decided to do OS upgrade as follow:
from 6.3.5 to 6.3.9 then 6.3.21
The upgrade to 6.3.9 worked fine and the main issue seems to be solved, but when we had done the second upgrade the device stucked and it is not accessible through ssh or http and also doesn't respond to ping request.
How can we revert to 6.3.9 again without uploading it through ftp? or any recommendation will be appreciated.
the main issue