On Fri, Feb 19, 2010 at 12:49 PM, Jean-Francois <jfsimon1981@gmail.com> wrote:
...
quoted text
> Not sure to understand the subtle of the man page explanations regarding the
> dump of different nature of mount points.
>
> Just one additional information, the dump of higher levels work when I dump
> /var but not /var/htdocs.

The key is the last sentence of this paragraph from the dump(8) manpage:
     files-to-dump is either a mountpoint of a filesystem or a list of files
     and directories on a single filesystem to be backed up as a subset of the
     filesystem.  In the former case, either the path to a mounted filesystem
     or the device of an unmounted filesystem can be used.  In the latter
     case, certain restrictions are placed on the backup: -u is ignored, the
     only dump level that is supported is -0, and all of the files must reside
     on the same filesystem.

So, if you're not dumping an entire filesystem, then you always get a
full (level 0) dump.

(Why?  At least part of the reason is that if you're not doing the
full filesystem, inode ctime isn't sufficient to determine whether a
file would be new to the dump.)


Philip Guenther