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Moving from AFS Share to SMB Share - Problems with extensions and stuff.

Medium Priority
Last Modified: 2013-11-17
I have a group of people who access an AFS share running off of a Windows 2000 Server.  I want to take advantage of the Mac OS being able to access the Windows shares via Samba, but I have a little problem.

When the group accesses their data via SMB the program associations are broken.  Almost everything wants to open with Preview.  Additionally, the icon for the file, which normally shows the actual graphics in the file (This is a marketing office so we're talking mostly photoshop and illustrator), now just shows a generic icon.

If they create a new file and save it on the SMB share, the program association as well as the icon work correctly.  It's just for the 250Gb of data that was created while connecting via AFS that is a problem.

My goal is to have these users connect using SMB, and have the icon and program associations repared.  Hopefully there is a utility or something out there that can go through those files and fix accordingly.

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I'd say the problem is handling of resource forks on the two different systems (see http://en.wikipedia.org/wiki/Resource_fork for a discussion of Mac file forks). Macs have traditionally used filetypes and creator codes metadata (see http://en.wikipedia.org/wiki/File_format#Apple_Macintosh_type-codes) for file associations, and these are stored in the resource fork, as are Photoshop previews.

Under the AFS share, Windows is natively supporting the storage of resource forks - the local OS is able to hand over all of the native data it's been passed by the program and the resource fork storage is then handled by Windows.

Under the SMB system, the local OS recognises that there's no native support for resource forks, and so it passes two files to the server - the original filename.ext, as well as a dot underscrore file like ._filename.ext - dot files are invisible to the user by default in OS X, but when the OS sees them, it knows they're there and it knows how to interpret dot underscore files as resource files.

So, when you access the previously stored data under SMB, the dot underscore files aren't there, so you don't see the icons and associations. New files are given the appropriate metadata through the dot underscore file.

Just about the only way I can think to get past this is to copy the data off the server when connected via AFS, then copy it back to the server when connected via SMB - the SMB clients will then have the data they need. This is most likely a weeekend task, and you'll also then lose the AFS metadata in the process.

Hope that's of use


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Thanks for the help.  The link below is for a tool that will actually combine the data streams into 1 file making it impossible to lose the enhancements.  With AFS, resource forks and data forks get messed up all the time.  With SMB, if the file gets seperated from the ds_store file, the same thing happens.  So neither of those are really perfect.

This tool is good, except it is 3rd party which I like to stay away from, and it is expensive.  I run my mac volume on a Microsoft cluster, so their product would run me about 10K which is a bit much.


Oh well, maybe later versions of the Mac OS won't have this weakness.
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