On Thu, Aug 28, 2008 at 4:43 PM, Matthew Woehlke
<mw_triad@xxxxxxxxxxxxxxxxxxxxx> wrote:
I didn't say anything about cross-filesystem... but bind mounts can put
one hunk of an FS in one place, and another somewhere else (and I don't
know of any reason a hardlink couldn't span this since it's still the
same physical FS). Similar with NFS mounts, the 'same filesystem' would
apply, I assume, the the server, which need not export the entire FS.
Wait. I did't understand you correctly. 'mount --bind' allows you to place on chunk of a file system somewhere else. As a result, /home/ftp and /home/someone/ftp (as a use case is to allow ways out of chroot jails) may be the same physical directories. In that way, yes 'mount --bind' is similar to hard linking. NFS, of course, can be used to allow a file system to be accessible to two computers. However, 'mount --bind' and NFS are all on top the the physical file system, in the VFS. Hard links exist in the physical file system, so for example, hard links don't work on some file systems (i.e. Windows ones), similar to symbolic links which are also part of the file systems. Also, 'mount --bind' and NFS can easily be traced (just run 'mount' and you'll see both of them).
And yes, it should be possible to hard link between files on multiple 'mount --bind' links, as long as they are both on the same physical file system. However, I just tried it and it didn't work.
--
Michael Howell
mhowell123@xxxxxxxxx