There will be no change in Tally.ERP 9 synchronisation in a Tally.Server 9 environment.
In fact, users benefit from Tally.Server 9’s ability to facilitate concurrent usage of Tally data - users can read (e.g. view reports) and write (e.g. record transactions) data and perform Data Synchronisation continuously with no interruptions in between.
Illustration
National Traders has its Head Office in New Delhi and a Regional Office in Bangalore. Financial data recorded at the Regional Office is periodically updated to the Head Office using the synchronisation facility in Tally.ERP 9. National Traders uses Tally.Server 9 for sharing Tally data.
Regional Office: Users A, B and C work at the Regional Office. A is a data entry operator, and records transactions here in the Regional Office. B is the Head Accountant and supervises his subordinates. C is the Manager and performs the synchronisation of Tally data with the Head Office.
Head Office: User D is at the Head Office and does synchronisation of data from here. Users E and F also work at Head Office.
Now, with the installation of Tally.Server 9, all of this happens simultaneously. Hence, C and D can do synchronisation with no interruption from the activities of A, B, E and F.