Traditionally tar(1) was used as it preserves most metadata. Modern versions even include optional support for ACLs and extended atributes (xattr). It used to be common to see command lines and scripts that piped "tar c" into "tar x" directly as a way of copying files while utilizing tar's metadata-preserving features.
Today, back-to-back tar is rarely needed, as cp itself already has options to preserve metadata. In particular, "-a","--archive" turns all the normal features (including --recursive), making metadata-preserving backups as easy as:
Just the "-a" option is enough for most simple local backups. Fancier backups are possible with cp's "--backup=numbered" and --reflink=auto features, but my favorite just-works solution for backups is rdiff-backup[1]. It preserves everything, uses rsync internally for minimal data transfer on incremental backups, and many more features.
I'm a big fan of fsarchiver (https://www.fsarchiver.org/). I've successfully used it for restoring full Windows 7 systems (NTFS), which implicitly requires getting all the metadata correct (e.g., alternate data streams).
Hopefully at some point you will mention the fact that not everyone has the same idea about what a file is (streams, extended attributes) or what metadata is (ACLs, versions, other timestamps)...
A discussion of extended attributes, ACLs and security labels (if you want those too) appear to be missing?
These things are a deep dark pit of problems and it isn't entirely unreasonable to just give up on them, but every once in awhile someone tries to do something useful with them so it's at least important to be aware that they exist.
Don't forget MS NTFS files support multiple data streams [1] and OS X supports resource forks [2]. I dislike both of these partly because they don't fit within the set of posix commands and command options I'm familiar with.
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[ 97.7 ms ] story [ 528 ms ] threadHere's the whole list: http://yakking.branchable.com/tags/move/
Long ago, I assumed that backup (and move) applications are relatively simple. But it has never seemed to work out that way.
Today, back-to-back tar is rarely needed, as cp itself already has options to preserve metadata. In particular, "-a","--archive" turns all the normal features (including --recursive), making metadata-preserving backups as easy as:
which is a shorthand for Just the "-a" option is enough for most simple local backups. Fancier backups are possible with cp's "--backup=numbered" and --reflink=auto features, but my favorite just-works solution for backups is rdiff-backup[1]. It preserves everything, uses rsync internally for minimal data transfer on incremental backups, and many more features.[1] http://www.nongnu.org/rdiff-backup/
http://www.sentex.net/~mwandel/jhead/
These things are a deep dark pit of problems and it isn't entirely unreasonable to just give up on them, but every once in awhile someone tries to do something useful with them so it's at least important to be aware that they exist.
[1] https://technet.microsoft.com/en-us/library/cc961812.aspx
[2] https://en.wikipedia.org/wiki/Resource_fork