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0 pointsnix234y ago0 comments

How is that possible?

0 comments

I read that some of the key information is in attributes unique to Apple's file systems, I can't find the source but that was my conclusion after trying to figure out what went wrong in the Time-Machine/Synology/Rsync-via-webdav system I set up for my father some years ago.

If you rsync ext4 files to exfat, you also have issues, but those are very clearly reported when you attempt to do so.

nix23OP4y ago

It makes sense that you loose some information from a posix filesystem to exfat, but from HFS+ to lets say XFS? Both can have extended attributes..hmm

However hold on, i do some research. Now you hooked me ;)

EDIT: Ok got it, both Filesystem NEED xattrs enabled, and you need to run rsync with the -X or --xattrs option, that should fix the problems.

formerly_proven4y ago

Extended attributes are messy. E.g. the equivalent on Windows (ADS, not EA, which also exist separately) can store arbitrary amounts of data, I'd expect resource forks on macOS to be similar. Meanwhile Linux only supports 64 KB of data for them, though most Linux-native file systems have an even lower one block limit. And then there's Solaris where extended attributes are actually an FS namespace.

So even if both file systems support extended attributes, does not mean that you can actually preserve them.

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teekert4y ago

I was hoping to hook someone, looking forward to what you find :)

j / k navigate · click thread line to collapse

0 comments

teekert4y ago

If you rsync ext4 files to exfat, you also have issues, but those are very clearly reported when you attempt to do so.

nix23OP4y ago

It makes sense that you loose some information from a posix filesystem to exfat, but from HFS+ to lets say XFS? Both can have extended attributes..hmm

However hold on, i do some research. Now you hooked me ;)

EDIT: Ok got it, both Filesystem NEED xattrs enabled, and you need to run rsync with the -X or --xattrs option, that should fix the problems.

formerly_proven4y ago

So even if both file systems support extended attributes, does not mean that you can actually preserve them.

1 more reply

teekert4y ago

I was hoping to hook someone, looking forward to what you find :)

j / k navigate · click thread line to collapse