[Libguestfs] [PATCH 3/3] RHEV: Cleanup volumes on unclean shutdown

[Richard W.M. Jones]

On Tue, Jun 08, 2010 at 03:55:50PM +0100, Matthew Booth wrote:
> Currently image files will be left on the export domain if a conversion fails.
> It isn't possible to delete these through the RHEV UI, requiring an
> administrator to clean them up manually.
> 
> This change causes images to be written to a temporary directory on the export
> domain, and moved to the correct location immediately before writing the OVF
> file. It also removes this temporary directory automatically on unclean
> shutdown. This means that a failed conversion shouldn't leave anything on the
> export domain. Even if it does, for example because of a power failure, the
> temporary files are clearly separated in their own directory.

The patch is fairly confusing because of the use of NFSHelper, but I
have two potential concerns:

(a) I don't think Perl 'rename' function will work if the temporary
directory is on a different filesystem from the final destination.
You might be better off using the 'mv' shell command (possibly with
suitable shell quoting) instead.

(b) Where is $tmpdir typically?  If it's on /tmp you might find you
have limited space, eg. if /tmp is a ramdisk.  (We have the same
problem in libguestfs, and people can override it by setting $TMPDIR).

Rich.

-- 
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