File Under: Web Services

Amazon Glacier: Back Up All Your Data for Pennies a Month

Amazon Glacier: your files, on ice. Image: Christine Zenino/Flickr

Amazon’s newest web service is custom-made for anyone paranoid about data backups, and now that you know Mat Honan’s I-was-hacked story, that’s everyone right?

Amazon Glacier, as the new service is known, stores a copy of your data in archived format for less than a penny per gigabyte per month. The only catch is that getting the data back out can take some time since Glacier is primarily intended for backup and long-term storage.

Unlike Amazon S3, which is designed for cheap but accessible file storage, Glacier is, as the name implies, playing the long, slow game. Glacier is intended for data you don’t need to get to often — database backups, images archives and the like. In the press release Amazon also says that Glacier data is intended to last, as in “centuries.”

Here’s how it works:

To store data in Glacier, you start by creating a named vault. You can have up to 1000 vaults per region in your AWS account. Once you have created the vault, you simply upload your data (an archive in Glacier terminology). Each archive can contain up to 40 Terabytes of data and you can use multipart uploading or AWS Import/Export to optimize the upload process. Glacier will encrypt your data using AES-256 and will store it durably in an immutable form.

While there’s an obvious use case for enterprise web services and any digital archiving project, Glacier could also be used as a cheap way to create an off-site backup of your files using something like Arq That would make Glacier not just a long-term storage partner for S3, but a competitor to backup services like CrashPlan or Backblaze.

[Update: Stefan Reitshamer, creator of Arq, tells Webmonkey that he's looking into adding support for Glacier to a future version of Arq. However, he also points out a couple of potential gotchas to using Glacier for personal backups, namely the possibility of very expensive transfer fees (see the discussion on Hacker News for more on this) and fees for deleting data less than 3 months old. It's also worth mentioning that Amazon's own blog notes that in some cases it may still be cheaper to use S3.]

Amazon also says that an S3-to-Glacier file moving tool for automated backups is in the works.

It’s important to note that getting your data out of Glacier is priced a bit differently than what you might be used to with S3. With Glacier you can retrieve up to 5 percent of your average monthly storage, pro-rated daily, for free each month. After that prices start at $0.01/GB. For full pricing details check out the Glacier pricing page.