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A developer uses a cold data cloud service such as Amazon Glacier to move infrequently accessed data to archival storage to save money on storage costs. He can also move database backups from tape storage media to the cloud for long-term Glacier storage.
Glacier vs. Amazon S3
Amazon Glacier provides durable storage for any type of data format that will be accessed in three to five hours. A developer could use Amazon Glacier in conjunction with storage lifecycle management, rotating rarely used data to cold storage to save money. Glacier differs from Amazon's more expensive Simple Storage Service (S3) in that S3 is designed for data that needs to be retrieved in real-time.
An enterprise turns to Amazon S3 for object storage with low latency. S3 is a better fit than AWS' Glacier storage for an enterprise that requires regular or immediate access to data.
Archives and vaults
Amazon Glacier stores data in archives and vaults. An archive is a block of data that may consist of a single file or aggregated data in the form of TAR or zip files. Glacier archives range in size from 1 byte to 40 terabytes (TB); there are no limits to how much data and how many archives an AWS user can store in Glacier. Amazon offers a multipart upload feature for higher throughput and reliability for archives over 100 MB.
An AWS user can group archives together into a vault, which helps organize data. A user selects a host vault for each archive and can manage access to that vault via AWS Identity and Access Management (IAM) and can attach notification policies to vaults. An administrator configures a resource-based access policy to each vault, governing who can access a specific set of archives and how they are accessed.
A vault lock also helps achieve compliance for each lock. Once a vault locks, Amazon Glacier enforces preset configurations to ensure it meets compliance standards.
Amazon charges per gigabyte (GB) of data stored per month on Glacier. While uploading data to Glacier is free, Amazon charges a fee for a retrieval request that's more than 5% of the customer's average monthly storage. This is meant to discourage customers from using Glacier as a general online storage service.