I found only these two statements from BOL regarding this Initial Data Synchronization method:
Link 1
Automatic seeding uses the log stream transport to stream the backup using VDI to the secondary replica for each database of the availability group using the configured endpoints.
Link 2
During automatic seeding, SQL Server performs a backup over the network for initialization.
Looking into SQL Server Error logs of both primary and secondary replicas, these two logs caught my attention:
On primary replica
On secondary replica
My question is related to the working nature of automatic seeding, namely where does taken backup is stored before restoring on the secondary replica?
