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The following table shows the available combination of cluster size, volume count, and single volume size for an HDD cluster of st1.
Cluster size | EBS volume count per node | Single EBS volume size (TiB) | Cluster raw capacity (TiB) | Approximate usable capacity percentage |
5 | 4 or 10 | 80 or 200 | 50% | |
5 | 5 | 4 or 10 | 100 or 250 | 60% |
6 | 5 | 4 or 10 | 120 or 300 | 67% |
4 | 6 | 4 or 10 | 96 or 240 | 50% |
5 | 6 | 4 or 10 | 120 or 300 | 60% |
6 | 6 | 4 or 10 | 144 or 360 | 67% |