I have gone through several guides regarding the subject topic .I would request your views regarding the below.
1.To perform backup the system needs to be online ,it is not possible to take back up while the system is offline.
2.Is there any limitation on number of standby servers ,there can be max 3 master servers in a landscape.
3. As of now we can perform data back up, log backup,configuration backup and also we can perform point in time recovery.
4.For the stand by server to become active in case of failure of existing index server no manual intervention is required it happens automatically.
5.In case of disaster tolerance the other data center would become active automatically.(or any manual intervention is recovered.)
Request you to share your views and correct me if I am wrong.