> On Nov 11, 2015, at 2:55 PM, David Simpson <[email protected]> wrote:
> 
> Hi all,
> 
> Thanks for the help so far. This has saved me a lot of time.
> 
> I have a fair amount of data I'm looking to copy (potentially ~30TB) - that 
> is data from multiple file-servers to multiple tapes and without LEOM. Am I 
> correct in saying this is the implication(?) - Amanda will get so far through 
> the disklist then realize it can't fit a DLE onto a tape then load the next 
> [correctly labeled] tape?
> 
> 
> I will be loading 8 LTO6  tapes into the tape changer (currently max 
> capacity). I only have this one tape changer at my disposal.
> 
> I'm looking to do two things with the same data:
> 
> 1) perform a one-off archive and remove the tapes for safe storage off-site
> 2) load a new set of tapes and use amanda as a near-line storage solution 
> (quick backup/restore over network)
> 
> Both of these can be achieved with the identical config I think? I just need 
> to specify the exact days for 1) then remove the tapes... before doing so, 
> will i need to use amadmin to say do not re-use these tapes? (incase I 
> retrieve from safe storage to do a restore from)
> 
> Does this sound sensible?
> 
> dumpcycle 1 week
> runspercycle 5 
> tapecycle 8         ?

To address only THIS part of the question:   I would recommend a MINIMUM  of
   tapecycle 15    # 3 weeks   - 5 runs times 3 weeks.
and if you can manage it
   tapecycle 20      # 4 weeks  - 5 runs times 4 weeks.
 or more.      If you use one tape per night   (runtapes 1  is the default;   
you didn’t mention how many you need?)     then you are only giving yourself
half a week before you overwrite your last full backup.   8 tapes means you are 
overwriting a full backup BEFORE you write another full backup, 
and you might not be able to do a restore.   Amanda doesn’t promise on WHICH 
day any one DLE will get a full done.   So maybe the DLE
that you need to restore today doesn’t have ANY full because you overwrote it 
last night?   (Yeah, I just said that, didn’t I.)

My philosophy is  “if the data is worth anything at all to us,  then it is 
worth buying enough tapes to have at least 4 weeks of backups”. 
I’ve got a 10 week rotation of tapes right now.

Deb Baddorf
Fermilab




> 
> cronjob to invoke amdump once sun-thur inclusive at night ... any new DLE 
> configured fri, meaning full backup of new DLE performed sunday
> 
> 
> thanks
> David
> 
> --------------------
> David Simpson - Computing Support Officer
> IBME - Institute of Biomedical Engineering 
> Old Road Campus Research Building
> Oxford, OX3 7DQ
> Tel: 01865 617697 ext: 17697


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