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Re: Question about Running rsnapshot




I am replying to two messages at once.

Andrew McGlashan <andrew.mcglashan@xxxxxxxxxxxxxxxxxxxxx> writes:
> Is it this:
> 
> https://www.microchip.com/SWLibraryWeb/product.aspx?product=Memory%20Disk%20Drive%20File%20System
> 
> ????

	I just realized that I goofed when I wrote the name of
the application that combines multiple drives in to one large
drive.  I meant
    mhddfs for example:
    mhddfs /rsnapshot1,/rsnapshot2 /var/cache/rsnapshot -o mlimit=100M >/dev/null 2>&1 

The file systems used on these drives are Linux file systems and
are mounted ext4.
Greg Wooledge <wooledg@xxxxxxxxxxx> writes:
> Two (or more) hardlinks to the same file can only exist within a file
> system.  If /a and /b are separate file systems, then it is completely
> impossible for /a/file and /b/file to be hardlinks to each other.

That's what confuses me right now as this obviously works as I
can go to all of those backup directories and cat that file or
any of the several thousand other files in the backup and read
their contents.

	I had a look at rsnapshot which is a perl script and the
line that makes the link is:

		print_cmd("ln $srcpath $destpath");

Maybe I am confused about what produces a hard link but I thought
that did.  It ends up looking like all the blocks of that file
are in that directory when in fact we are reading blocks that
were only written once and only seem to be in multiple file
systems.

Martin