The most particular case about migration is the downtime, estimate the windows that customers need to achieve and perform a good project, but this not always happen and with the native HANA methodology of HANA System replication (HSR) we can mitigate some risk about Downtime, but as you well know to execute HSR is necessary to have the same SID in both HANA Nodes (and others prerequisites – help.sap.com – General prerequisites for HANA System replication), when the customer already have the same SID of HEC/RISE is good because we review the others prerequisites and we can move forward but when the it cannot be completed we will face issues and the downtime is impacted.
One of this common scenarios is when a customer has already on HEC all infrastructure and wants to move on RISE Contract, if the SID of BD HANA for example is D01 On premise and RISE is D10 and 10TB of size in HANA DB and the Business windows is just 24hrs, in this scenario we cannot move with HSR and is when enter Tenant Replication (Copy / Move) , with this new feature in HANA DB we can move or copy a tenant in few hours (Depend of the bandwidth), for this case mentioned above is possible with good VPN of 100MB/s transfer the tenant to RISE in just 4 hours and later perform the finalize replica and startup the HANA DB in the new target (RISE), then we will proceed with the next steps in app server, post migration and deliver to RISE for post activities migration, we can explain in more details but first we need to fill the prerequisites: