Hello Community,

We’re going to migrate file servers to different hardware with new hostname, while keeping the same drive letter, data/content.

Subsequently, once these new servers install/config into the Commvault, they will be linked to the identical storage policy that the old servers were associated with. This storage policy with ddb enabled

From my understand, Commvault's deduplication process use a SHA-512 algorithm, which generates a unique identifier for each data block. This identifier is then matched against identifiers of previously encountered data blocks.

Questions:

1. I'm wondering whether, during the initial full backup of the new file servers, the data will undergo a process of re-baselining, or if only distinct data blocks will be selected for backup. This consideration arises from the fact that the same content and deduplication (ddb) signatures were previously backed up or generated from the old servers. Moreover, this inquiry leads to the question of whether the new full backup will make use of the ddb signatures from the old server's data blocks, or if it will generate new ddb signatures/re-baseline, given that this is a new server.

2. Additionally, is there a method/formula  available to estimate the expected storage space needed for the new file servers when taking deduplication into account?

thanks