if you are okay with backups being restored within 12 hours, than you can consider the following. If the minimum of Commvault Backups is the Full’s Size, than that is the easiest way to calculate it over the long term, but there are additional tricks you can take in the cloud to spend even less.
Scenario: I would like to retain backups for 12 months in US-EAST-1. Which backup tier will cost the least? if the Cost from S3 Tiers from most expensive to least expensive per TB/month is $24, 12, 4, and 1 ( S3, S3 Inactive, Glacier, Glacier D.A). if we are using Deduplication/ Synthetic Fulls in this scenario, over 12 months the most ideal tier is S3 IA. As archive tiers cannot combine “Fulls” through Synthetic fulls, we simply to have to store more fulls times the number of months of retention.
Ex. S3 = $24 x 1 ( syn. full ), S3 IA ( syn. full ) = 12 x 1, S3 Glacier = 4 x 12, S3 Glacier D.A = 1 x 12. 12x from S3 IA is the same as S3 Glacier D.A, but it would make more sense to choose the tier that allows for faster restores. In this case, it would cost $12/TB a month in addition to running the Mediagent for about 7 days a month to make it a grand total of Cost = $20 ( M.A cost for stores less than 50 TB ) + $12 * the Amount of TB.
Scenario 2: Hey, its true that S3 IA can be the least expensive, but can you go even lower than that? – Yes, you can. If you use 1 backup set for local retention that has faster restores and simply just need a solution that allows for long term retention for compliance reasons, you could in theory just use the Commvault Combined S3 IA / Glacier Tier to get costs pretty low. You could get away with just having 1x Fulls in Glacier D.A. and get a cost factor of nearly 1.10x in the states and about 2.10x everywhere else.
Ex. i store 10 TB of Data. My costs could be as low as $10/month for storage and it will cost $20 to have the Commvault Media Agent only be on 7 days in that whole month for a total cost of $30/month to store the data. I will create 1 Full per a year and the rest of the months will utilize an Incremental backup.