1) Open Putty / SSH / or Console to the VDP
2) Run the command 'emwebapp.sh --restart' (two hyphens in front of restart).
3) Allow for a couple of minutes after the output of the above command completes and try again.
4) If this does not resolve the issue, then look at the /usr/local/avamar/var/vdr/server_logs/vdr-configure.log and see what it has in there around the FLR services stopping.
Hope this helps.
Greg