Netbackup appliance 5220 2.5.4 maximum usable percent puredisk

[pedro_centol]

Hello team.

Can you provide me, what is the maximum usable size in a puredisk on a appliance.

Server Type	Used Capacity	Available Space	Raw Size	Usable Size	%Full
AdvancedDisk	7.05 TB	3.52 TB	10.57 TB	10.57 TB	66.70 %
PureDisk	52.44 TB	8.97 TB	61.41 TB	61.41 TB	85.40 %

Now we have to make backup of a resource of 6TB. There are space enough? at puredisk.

Thanks & Regards.

[Mark_Solutions]

That depends on what the 6TB resource is .. if it is data that de-dupes well or is very similar to data you already have backed up then it may not add much to your de-dupe pool.

The Advanced disk and de-dupe are governed by their high watermarks but in my experience we dont like a de-dupe pool to be more than 80% full otherwise its processing power falls off rapidly and if it does get somewhere near full then it causes real issues with queue processing etc.

As you are already at 85% on your de-dupe pool i would be reluctant to add any more .. but you could try processing your queue through a few times over a couple of days until it is right down in size .. you may find that you suddently get some extra space back!

Of course if you go to 2.6.0.2 you can add another shelf or two!

[chashock]

I'd be careful adding that 6TB.  You're already over the 80% recommendation and if that data doesn't dedupe well, you're going to push that pool beyond its ability to perform maintenance tasks.

[fredouille]

Hi, where can I find these recommendations ? Dedupe_admin_guide talks about 4% reserved for logs/DB but there is nothing about 80% max used for dedupe data repository.

Thks.
 

[Mark_Solutions]

The official word is actually 85% but in practice we see a drop off after 80%.

See the first line on page 102 of the performance guide:

http://www.symantec.com/docs/DOC6745