09-08-2014 10:43 PM
NBU 7.5.05
first time creating a pool. i came across the question of "retention period". if i select "infinity", would that mean:
regards,
rino
Solved! Go to Solution.
09-08-2014 11:07 PM
retention period is designed for backup image, not the media tape.
So what setting to "infinity" means is that the image written onto the tape will never expire, so it will consume your media tape capacity.
If a tape is FULL with many images of infinity retentiion period, the tape will never get reused until you expire some images inside.
If a tape is half-full with images of infinity retentiion period, you can still write some more images onto it until it becomes full.
There is a separate way to set media tape "expiration", on the media level via Netbackup, it is different from what the retention period means.
09-08-2014 11:07 PM
retention period is designed for backup image, not the media tape.
So what setting to "infinity" means is that the image written onto the tape will never expire, so it will consume your media tape capacity.
If a tape is FULL with many images of infinity retentiion period, the tape will never get reused until you expire some images inside.
If a tape is half-full with images of infinity retentiion period, you can still write some more images onto it until it becomes full.
There is a separate way to set media tape "expiration", on the media level via Netbackup, it is different from what the retention period means.
09-09-2014 12:30 AM
hi, ok will proceed with my original plan.
thanks.
09-09-2014 10:47 AM
Think twice before you select 'Infinity'.
Do you really have a requirement for 'Infinity' retention or are you selecting this retention because NBU does not have a built-in 5- or 7-year retention?
If you did not know this - Retention levels can be customized in Host Properties.
09-09-2014 11:47 AM
Expiring images on a tape does not necessarily create room on the tape for more images. NetBackup will only append images to an existing tape. Only by expiring the very last image on the tape can you make space available for reuse. Not much to gain there.
Always try to minimize retention period. In the US if you have data on a tape that may pertain to a litigation then you may be legally bound to restore the data.
Infinite retention can cause headaches if the data is not hydrated when new tape drives or backup solutions are entered into the environment. You may think you have data BUT can you restore it?
09-10-2014 01:09 AM
i specifically chose "Infinity" based on finance requirements.
but now that you mentioned that retention levels can be customized, how can i do that please?
09-10-2014 01:31 AM
Host Properties ->Master Server -> Retention Periods.
More info in NBU Admin Guide I, Chapter 3: Configuring Host Properties
09-10-2014 01:39 AM
the thing is, finance have no policy on up to how many years to keep data. so we have to just archive them for an indefinite amount of time. we don't want to lessen retention period then 5 years from now found out that we can't restore because the image has expired.