Use of Scratch pool

You may set the scratch pool as default volume pool on inventorying robot, by below bar code example rules.

Barcode tag: <DEFAULT>

Media type: hcart3

pool name:  Scratch Volume Pool

All backups will be using the media from scratch pool and hence at the end of backup you may run a report and track the media usage.

You can have only one Scratch pool configured with NetBackup.If a Scratch pool is configured, Media Manager moves volumes from that pool to other pools that do not have volumes available.Once those volumes become unassigned, those will be returned back to Scratch pool by Media Manager. If don't want those volumes to come back to Scratch pool you can use the following command to disbale that feature:

nbemmcmd -changesetting -return_unassigned_media_to_scratch_pool no -machinename <EMM host>

NBU serches for volumes in the assigned pool first and if not available it searches in Scratch pool for usable media.

Also You should not configure policies to use Scratch Volume Pool.

Regards.....

"This is our majority requirement as we are given media's by different app owner. and pools are created accordingly."

As mentioned in the first reply, NB can only have one scratch pool from which all backup jobs could call media if required. You would have absolutely no control over which media is called by which job which I think is what you require? If your "cilents" (customers) are determining which set(s) of media to use for which jobs then you'll just have to ensure that each pool has enough media to cater for your upcoming jobs.

A scratch pool will certainly help to alleviate status 96's.

Extract from Admin Guide I:

About scratch volume pools
The scratch pool is an optional pool that contains the media that NetBackup can
allocate to other pools as needed. If you configure a scratch pool, NetBackup moves
volumes from that scratch pool to other pools that do not have volumes available.
Only one scratch pool is allowed.

When you create a scratch pool, you can call it anything you like, as long as you select the 'scratch pool' tick box. It just makes sense to call it something like Scratch.

It will require that you manually change all unassigned media to scratch. You will have to keep on doing it as and when images expire and media returns to unassigned. This is a once-off task for all media. After this, media will automatically be returned to scratch upon expiration. The following setting is enabled by default:

# nbemmcmd -listsettings -machinename <master> |grep -i scratch
RETURN_UNASSIGNED_MEDIA_TO_SCRATCH_POOL="yes"

You can also add a Barcode Rule for all new media to be put into Scratch Pool.

NetBackup will never search the NetBackup pool unless this pool name is explicitly specified in the policy.

how netbackup search media:

1. assigned pool
2. scratch

More info: http://www.symantec.com/docs/HOWTO32854

hi Zahid,

If i use scratch pool, what should be configured in policy

for notification i would require media ID and policy name which had taken media from scratch pool.(If policy is configured without scratch pool)

This information helps us to track the usage of media. and for restoration purpose also.

if notification is not possible then it becomes difficult for admin to track media usage.everytime admin would need to open job propertise and from details pane he would need check for media used. this manual intervention would be time consuming along with day to day regular activities.

Cheers

Vaibhav

If i use scratch pool, what should be configured in policy

You dont need to configure any thing in the policy. When your Media will full the Netbackup will automatically go to search the Scratch Pool to find the Media

for notification i would require media ID and policy name which had taken media from scratch pool.

If Netbackup writes any Error/Warning/Info( which i am not confirm) in the Event Viewer when the media being assigned from scratch pool in case of existing Media Full then i think i may possible. See the below Blog it may help you i hope.

https://www-secure.symantec.com/connect/blogs/howto-check-netbackup-tape-drive-status-and-generate-email-alert-once-any-drive-down

OR

try to use and search Opscenter admin guide

Hi Zahid,

"in OPs Center we need to execute query" this was statement by Sym Support. Though assigned engg told that using query we can get this details but we need to identify which table does it points to.

i thought this would be available in OPs Center but didn't got any reports which gave give this details.

For scratch pool i believe your point of view comes after my existing media is full.

but i'm asking at beginning of backup will netbackup pick any media from scratch pool.

"at beginning of backup will netbackup pick any media from scratch pool."

Only when there is no suitable media in the required pool to write to.

See Admin Guide I:

"NetBackup moves volumes from the scratch pool to other pools that do not have volumes available."

Also see http://www.symantec.com/docs/HOWTO32854

Hi Vaibhav,

By now you probably realize how effective a Scratch pool can avoid error 96, but I think your dilemma to implement is that how you are going to track the media usage for each business unit, because you simply don't own the media. Your business unit purchase them for you, based on reported usage.

From my experience, when we talk to different business unit we don't give them media usage but data usage. It makes more sense and is perfect for us to use Scratch pool.

We ask them how much data they want us to backup, and we calculate the min. amount of media they need to purchase. In this case, we will have a bunch of media from each business unit and it's up to us to manage & use (put all media into Scratch pool). Business unit does not really need to know what tapeID they use, but they want to know how many media they need to or had purchased - about $$. That's all.

That will make life easier, for us and for them :)

My 2 cents.