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Click "Next: Add storage"

Add storage:

Root /dev/sda1 -snap- 8GB vol type = magnetic, delete on termination, not encrypted.

add another -

type = EBS, device /dev/sdb, no snapshot, size=500 (min for st1. You should be on the "Step 4: Add Storage"

For the existing root volume, set the following options:

Size: 8GB

Volume type: Magnetic

Select "Delete on termination"

Click "Add New Volume" and set the following options:

Volume Type: EBS

Device: /dev/sdb (take the default)

Do not define a snapshot

Size (GiB): 500 (This is the minimum for st1 volumes), Throughput optimized HDD, throughput =  20 / 123 (can’t change) Baseline: 40 MB/s per TiB, no delete on terminate or encrypt

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