The number of objects created per day should include only those objects stored on optical, tape, or both media types. If several objects of different sizes are to be written to optical, tape, or both media types, calculate the number of megabytes written per day for each object size and sum the results to get the total number of megabytes written per day. See Table 1 for more information on this calculation.
Each cartridge can contain objects from only one Object storage group. Therefore, on the first day that optical, tape, or both types of storage are used, you will need at least one cartridge for each Object storage group. If you plan to create backup copies of objects, remember to calculate the number of cartridges needed for each Object Backup storage group (use the cartridges per day formula in Table 1). On the first day that your installation creates backup copies, you will need at least one cartridge of the appropriate media type for each Object Backup storage group.