The error occurred because you have to update the database as there are going to be new tables and such in it. So in your example you're new box would need to be running 8.73 and then import your DB. Then do the upgrade to v9.x (you can't bring an v8 DB into v9).

As far as importing vs. migration..that's tough to say. Are you going to implement sites and how much data is in your current JSS? Do you have a lot of policies and other configuration data? Starting fresh and importing the machines would allow you to revamp your setup if you'd like to clean things up and maybe change your workflows. If you're happy with your current setup and don't foresee making a lot of changes when you move to v9 then updating could be best.

hi

i don't have much things in casper for now... 20-30 policies... couple of packages... it was our development server...

but for sure you pointed it out... i tried importing V8 into V9....

but now is there a way to flush everything on my sql and install V8 on my new server and start over the process ?

on the new server :

flush all mysql database that did not work
install V8
import database again
update V9
start migration process ?

??

I just did something similar recently. In my setup I was able to log into the MySQL command line tool and do a drop database command to remove my database. Then using the installation instructions from JAMF create a new database and set permissions. That worked for me to get rid of all the testing work I'd done. (I'm not sure of your platform for particulars) Remove the v9 JSS and install v8 and you should be to a point to import your DB and prepare for upgrading it to v9.

I should clarify the drop database command is on your testing/dev server.