jithinraj :
In our organisation we use Microsoft exchange server now we are planing to move to Office 365, it have online exchange server.
So do we need the local exchange server any more if we move to Office 365 ?
No, you don't need your local exchange server anymore.
That's one of the "benefits" of Office 356. It all exists online, and MS manages it.
The "downside" is that it all exists online, so if your internet connection goes down, or is just slow...you can't do anything.