WAN Sizing
All Oracle database virtual machines should follow standard Zerto sizing recommendations by using the Zerto WAN sizing tool, available on the self-service portal. It is necessary to capture the write rate on all disks in the Oracle database VM to calculate the required bandwidth between the sites.
Zerto best practice: If backups are made on the Oracle database virtual machine to a local disk, Zerto recommends having the backups stored on a separate virtual disk set as a temp data disk during VPG configuration, similar to the recommendation to use a temp data disk for temporary databases. Otherwise, Oracle backups can cause nightly bitmap syncs as the virtual machine is writing a copy of the entire database to a backup file that is being replicated. In this scenario, if the dataset is too large for the WAN link or for the VRA to keep up, then the virtual machine enters a bitmap sync mode.