assuming this is your production grafana I would recommend you do the following
- spin up 2 clones of the current live grafana server. #1 as playground/sandbox and #2 as a backup
- upgrade #1 to v 9 and sort out and document any and all issues
- either make this clone #1 the now live and upgraded version or take lessons learned on the #1 and apply the upgrade on the live one.
- if all else fails you still have clone # 2
Upgrades are never easy but planning and documenting and trying things out not on the live server but sandbox is the best practice industry standard way of doing things for anything.
Welcome to big boys/big girls world.