From the main controller, go to the Network Elements form, tick the elements to sync, then click Sync... in the following window, first just click continue or OK, this will sync basic system and essential information only and verify SDS is working properly. This should complete with no issues, if it doesn't you might want to get a vendor with a certified tech involved, if it works, do it again except tick the box to select and allow it to complete, depending on your system size and load, this could take a few minutes or possibly hours.
Always make sure to to a complete backup of all elements first, just in case...
And backups and restores can be completed completely through the web interface, remember a restore, even if it is the same data, will cause 2 system resets, one manual and one automatic, and could take between 15 minutes and 2 hours, again depending on system size and traffic.