On Fri, Nov 11, 2005 at 09:32:01AM +0700, Olivier Nicole wrote:
> Hello,
> 
> I wonder if there is a set-up for Amanda to back-up files by inum
> rather than by filename.
> 

Well, remember amanda doesn't backup anything.  Dump and gnutar do.
tar traverses the directory/file tree and I'm certain has no such
capability because I just grep'ed the man page for inode and inum :)

But maybe dump.  I think it traverses the inode list.  When a file
name is changed the data for the file doesn't change, but the data
for the directory does.  So the directory itself does need to be
backed up.  However, the way a file is "moved" is to make a hard
link to the new name and then remove the original link.  This brief
switch of the link count from 1 -> 2 -> 1 causes the ctime for the
file to change.  And I think that would cause dump to backup the file.
Bummer.  Maybe dump recognizes the condition and only saves the inode.
Yeah, right.  But you could do some simple tests to make sure.

> The reason would be the following: I have one machine that receives
> all syslog possible for each and every of my Unix hosts. Syslog logs
> are rotated every night and I keep them for one year, the total size
> is about 13 GB. Due to rotation, file all.0.gz becomes all.1.gz, file
> all.1.gz becomes all.2.gz etc. Files do not change a single bit, only
> their filename change. But still Amanda ends up backing up all the
> files every night because f the change in name which is obviously a
> lost of time and of tape.
> 

What about an exclude pattern that would be something like "all.[1-9].gz".
So the all.0's would continue to be backed up, but after rotating would not.


-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
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