I'd like to know if anyone here can share your experience in migrating the Exchange Server on premise to the cloud (Office 365) with no downtime or issues to the end users.
My current situation:
Single AD domain
Exchange Server 2010 no DAG hosting 5000 mailboxes for 3000+ users online in multiple different geographical location in Australian continent and some few thousands in Europe Continent,
All email older than one year old is automatically archived by Symantec Enterprise Vault v10.
Can anyone please clarify my points below:
1. For High Availability, all mailboxes migrated to Office 365 will not require the Internal IT Staff to create or worry about DAG it will always be online with high availability in all different continent.
2. No need to worry about Windows Update to the Exchange Servers as this is fully transparent to the users and internal IT staff
3. Office 365 Exchange will not have any bug or issues with calendaring and delegate mailboxes since all mailboxes in the Office 365 will be patched automatically by Microsoft hence will be trouble free.
4. All email or mailboxes can still be downloaded for .PST offline archive using Powershell or fully archived by in house/on-premise Symantec Enterprise Vault.
5. migrating 13 TB+ of exchange mailbox DB can be done automatically by using Powershell to export / move mailbox over the business hours with no downtime.
6. email access and response for users located in different continent will be speedy with no lag since the Exchange on Office 365 is always available and accessible everywhere around the world.
Are those assumptions correct for hassle free Exchange server migration to cloud ?
I need to convince my manager that is the case with cheaper option of using Office 365 rather than managing it in house.