hello My company is interested in moving to the cloud using Exchange 2013 hybrid deployment , I have some concerns regarding high availability before embarking in such a solution , I will be grateful if anyone can answer my questions and if I can be directed to the right documentations :
1- What is the HA level and how HA is granted between On-premise and Exchange online , is it on the network link level ? in other words can On-Premise and Exchange online servers act as a geographically dispersed cluster configuration ??? active/active or active/standby ? are the mailboxes synced between ? can it be configured in such a way ? all MAILBOXES on premises to continually sync to cloud or vice versa ?
2-what will happen if connection between On-premise and Exchange online stop for a reason ? will exchange online users be able to send/receive emails ? what about on premise users ?? what is the failover/failback mechanism that can be implemented here ?
3-what if disaster strikes the on-premise data center ? can Exchange online take over and be managed by direct connection ? will on-premise users mailboxes be available on the Exchange online , a replication auto-sync kind of solution (almost same question as 1-)???
thank you,
Yacoub