In order to add storage disks of any variety to your SoftNAS instanceVM, you will need to create at least one storage account. Creating MSFT or Blob disks require different storage account types. In order to leverage more than the 500 TB per storage account limit, you will need to create several blob storage accounts. When creating your multiple blob storage accounts, you must then decide whether to leverage hot or cold storage. You cannot mix hot and cold storage within a pool, but you can provide more than one pool. In other words, you will need to know what configuration you intend to create, and plan your storage accounts accordingly. One SoftNAS on azure Azure instance can potentially require many storage accounts.
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For more information on storage for Microsoft Azure, see the following links:
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