Disk size expanded after hardware refresh

Hello Community,

I’m currently migrating a old Commserve to a new hardware, which has different host name and IP settings, also with CommServe upgrading (11.28 → 11.34). So I have folllowed this page for the hardware refreshing: 

https://documentation.commvault.com/2024e/expert/commserve_upgrade_with_hardware_refresh_overview.html

I used Recovery Assistant Tool when setting up the CommServe database on new hardware. Now it works fine. 

The problem is when copying backup files (CV_MAGNETIC) from old machine to new one, the size of file has expanded a lot (5TB → 10TB) on disk. I assume this is bacuase of using DDB. 

I have also copied the DDB content (CV_SIDB folder and icl_label.txt file) to the new machine, but with different drive letter(D:\SIDB → E:\SIDB). 

My questions are:

1. What is the best way to set up the DDB in new machine?
2. Can I reclaim the disk space after the DDB is running fine?

Thanks!