On Thursday 28 August 2008, Toralf Lund wrote:
>Gene Heskett wrote:
>> On Thursday 28 August 2008, Toralf Lund wrote:
>>> I've just moved a disk from one server to another without really
>>> changing anything with respect to how the clients see it; logically, the
>>> disk still represents exactly the same volume on the network. [... ]
>>
>> Unforch, what I'd call a bug in tar will cause it to be treated as a new
>> device.  Part of tar's detection code makes the device's assigned number
>> part of the new/old decision.  So it will be subjected to a full level 0
>> backup as a newly discovered disk.
>
>This is not really a problem. But I don't think I follow you. Perhaps I
>wasn't clear enough in my original post; the disk is physically the same
>as before, it's the *host* that has changed.

Correct, and that new host will in all probability, assign a different device 
major as it discovers the drive during bootup, even if the actual path is 
identical formatted.

To see what it is I'm referring to, do an "ls -l /dev/sd*" on both machines.  
Here the major is now 8, but at one point it was being bounced from 253 to 
252 depending on whether my USB Key was plugged in!

>I'd really like the DLE in 
>question to list the actual host it's connected to, and not some client
>that mounts the volume, so as to avoid sending the same data twice
>across the network. But if I change the DLE just like that, Amanda will
>think I'm backing up a new disk (won't it?), so I'll get two separate
>indexes for what's exactly the same disk, and if I want to recover a
>really old file, I need to remember to switch to the old index/hostname.
>Which is something I'd rather avoid.
>
>I'm mainly talking about an "archival" config without tape reuse, by the
>way. And yes, I do keep amanda indexes "from the beginning of time" for
>those, as the way I see it, without these, the tapes would be pretty
>much useless, since nobody would remember what was supposed to be on them...
>
>- Toralf

If you can afford to purchase and store the tapes.  Here, I need mainly 
disaster recovery (like when the nvidia binary blob decides to wipe the boot 
drives LSN0, something that has never happened when running an ati card and 
the radeon driver, but it took it only 12 hours the last time to trash / so 
bad it was a hour long hand exec of e2fsck to fix it so I could boot again), 
or keeping track of stuff when I update the distro.  I won't restart amanda 
after such an update until I have recovered all my pix and those parts 
of /etc, /home and /root required to keep my bank account accessible, that 
sort of thing.

No 'customer data' to guard as I'm the only customer. :)

-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
The number of feet in a yard is directly proportional to the success
of the barbecue.