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ACLs though powerful add additional complexity to the system and do have some limitations discussed further down this article. You will notice throughout the Bonsai Framework we add ACLs only when absolutely necessary.
Limitations
Support in Utilities Still Being Developed - For example, the version of GNU tar packaged with the OS may not back up or restore ACLs.
References
Good introduction from the Ubuntu docs - https://help.ubuntu.com/community/FilePermissionsACLs
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