/[resourceType]/$load. First can load multiple resource types from one ndjson file, second is more efficient, but loads only for a specific resource type. Both operations accept body with source element, which should be publicly available url. If you want to secure your import use Signed URLs by Amazon S3 or Google Storage.
/fhir/$loadaccepts data in FHIR format,
/$loadworks with Aidbox format.
$loaddoes raw upsert into resource table without updating history. If you want to store the previous version of resources in history, you have to set
update = true,with this flag Aidbox will update history for updated resources.