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I'm trying to share USB hard drive with msdosfs connected like this:

mount_msdosfs -o large /dev/da1s1 /mnt/usb

I can see mounted drive: /dev/da1s1 on /mnt/usb (msdosfs, local)

but when I'm trying to share drive via NFS my exports file:

/mnt/usb -network -mask

I'm getting error

freebsd mountd[871]: can't export /mnt/usb MSDOSFS_LARGEFS flag set, cannot export

freebsd mountd[871]: bad exports list line /mnt/usb -network -mask

Any clue how to resolve this issue besides changing msdosfs on drive for something else?

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up vote 2 down vote accepted

Large MSDOS filesystems are not supported as NFS exports on FreeBSD due to some implementation limitations. You could try if you can successfully mount the FS without the -o large option, but if that fails, you will be out of luck with NFS (but maybe you could try Samba instead).

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A. The FAT file systems can be exported, starting with the early 2.4 kernels, but if used extensively, it may cause grief. First, only those operations supported by the exported file system will be honoured. Operations such as "chown", "link", and "symlink" are not supported by these file systems, and will fail. Read/write/create etc., should be fine, as long as the files remain relatively unchanged.

The most serious problem is that the FAT filesystem layout does not contain enough information to create a lasting identity needed for NFS to create persistent filehandles. For example, if you take a file, rename it to another directory, trunctate it, and write new data to it, there is nothing stored in the filesystem that can be used to show that the resulting file is, in any sense, the "same" as the original file, and there is no way to find the new file given any details about the original file. Therefore, the Linux NFS server cannot guarantee that once you have opened a file, you can continue to have access to that file, if the file is modified in the ways given above. NFS may then be unable to locate or identify the file correctly, and so may return ESTALE errors.

This is taken from the Linux NFS FAQ and it also applies to FreeBSD (except for the Kernel 2.4 stuff of course). Just want to make sure you're aware of that stuff.

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