Weekly Tape Out with Virtual Synthesized Full Backup

[SeRo]

Hello everyone,

I'am calculating a new backup repository.

Used disk space will be 21 TB
3% CR
2:1 compr.
Backup modus - "forever forward incremental"
RP 14
10% growth (3y)
= ~30 TB

Now I want to do a tape job every week, with only the last full backup on it. Am I right, that the virtual synthesized full backup doesnt need any extra space on the backup repository? Are there any other facts that I am missing in my calculation?

[veremin]

At day scheduled for virtual full backup a tiny .vsb fill will be created in source repository. Though, its size is negligible as it does not contain any data, just pointers to data blocks.

Your estimations look solid. If you're not sure, you can leverage this tool to double check your findings.