Author: David Six Language: text
Description: Uses for extended attributes Timestamp: 2017-09-11 21:57:39 -0400
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  1. I have a few uses for extended attributes:
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  3. 1. Storing S3 Metadata
  4. If you want to store data from S3 locally without loosing anything, you need to find a way to store some extra metadata that might be included, including ALCs. Since the principals in S3 are not translatable to unix-style users, ordinary Linux filesystem ACLs won't work. In my use case, I convert the ACL to YAML and store it in an extended attribute. Then it can be read on the command line or converted back and applied if a file needs to be re-uploaded.
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  6. 2. Add bit-rot *detection* to a lesser filesystem
  7. While not a replacement for ZFS, storing the file's checksum in an extended attribute can ensure it is easily found when you want to verify the integrity of the data.
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  9. 3. Thumbnails
  10. I haven't attempted this (yet), but Linux and some (but not all) filesystems support extended attributes with values 64k long. That is long enough for a small thumbnail to be attached to the full-size version.
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  12. Thanks for the show and keep up the good work!
  13. David
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