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Usable and physical disk capacity by disk size
You cannot use the nominal size of a disk in your aggregate and storage system capacity calculations. You must use either the usable capacity or the physical capacity as calculated by Data ONTAP.
The following table lists the approximate physical and usable capacities for the disk sizes currently supported by Data ONTAP. The numbers shown are in Mebibytes (MiBs). This unit of measure is equivalent to 2 to the 20th power bytes. (MBs, in contrast, are 10 to the sixth power bytes.)
The physical capacities listed in the table are approximations; actual physical disk capacities vary by manufacturer. The technical documentation for your disks contains the exact physical disk capacities.
Disk size as described by manufacturer
Physical capacity (MiBs, approximate)
Usable capacity (MiBs)
100 GB SSD (X441A-R5)
95,396
95,146
100 GB SSD (X442A-R5)
84,796
84,574
200 GB SSD
190,782
190,532
800 GB SSD
763,097
762,847
300 GB Performance
280,104
272,000
450 GB Performance
420,156
418,000
500 GB Capacity
423,946
423,111
600 GB Performance
560,208
560,000
900 GB Performance
858,483
857,000
1.2 TB Performance
1,144,641
1,142,352
1 TB Capacity
847,884
847,555
2 TB Capacity
1,695,702
1,695,466
3 TB Capacity ( X308A, single-drive carrier)
2,543,634
2,538,546
3 TB Capacity ( X478A, multi-drive carrier)
2,891,588
2,811,241
4 TB Capacity (X477A, single-drive carrier)
3,815,447
3,807,816
4 TB Capacity (X480A, multi-drive carrier)
3,815,447
3,748,319

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