xfsdump and chattr +d : undocumented but really useful behaviour

["Gerard Neil" <xyzzy@xxxxxxxxxxxxx>]

I've been running a gentoo linux server (currently 2.6.15) using xfs
and xfsdump for a couple of years now.

I've just discovered that if the the no-dump (d) attribute is set on a
directory (using chattr +d), then any new directories/files created in
that directory automatically acquire the attribute too.

This is *really* useful when used in conjunction with xfsdump -e,
because it means I can easily exclude entire subtrees from dumps.

If this is really how the no-dump attribute is supposed to behave on
xfs, then I suggest documenting this in the xfsdump man page. The
current "excluding individual files" section is confusing with respect
to chattr +d, and certainly doesn't mention this useful behaviour. I
can't find it documented anywhere else, either...

Regards,

Gerard