Data Domain Question

Question

Hello      We are in the process of acquiring Data Domain and Avamar and I am trying reconcile the storage usage number for Data Domain. Reason is when management ask who is using what I can provide an answer that is credible. First we are getting great numbers and really like Data Domain/Avamar so no problems there. I will state what I believe and if wrong please let me know. When I run the command 'filesys show compression' I get a Post-Comp of 12744.4 GiB which is the amount of data for all backups at rest on Data Domain. When that number equals the amount of Data Domain storage purchased we will be 100% utilized on Data Domain and need to buy more trays.      I need to be able to determine what how much storage each mtree is using. I can run an mtree show compression mtree_name but that presents values for some number of days. The problem there is that with 30 days I don't know if that value is really representative of what is currently stored in that mtree since data older than 30 days may be present. If I run for 90 days then data may have been cleaned and no longer present so that value may not also be representative.      The other command I use is 'filesys show compression' and it gives g_comp and a l_comp value. I would expect that the l_comp value which as I understand is the data at rest on Data Domain(post compression and post dedup). My issue is when I run the command 'filesys show compression' against the mtrees the sum of their storage usage(l_comp value) is about 45% of the Post-Comp of 12744.4 GiB value. We plan on getting DPA.  I would really like to know from the command line how to reconcile the storage used by mtree so that I can correlate those numbers with the Post-Comp of 12744.4 GiB value. Any insight would be greatly appreciated.

christopher_ime · Answer

Firstly, welcome to the forums, and above all, thank you for being an EMC customer.

Please consider moving this question as-is (no need to recreate) to the proper forum for maximum visibility. Questions written to the users' own "Discussions" space don't get the same amount of attention and can go unanswered for a long time.

You can do so by selecting "Move" under ACTIONS along the upper-right. Then search for and select: "NetWorker Support Forum". There isn't (yet) a dedicated Data Domain community.

NetWorker Support Forum

NWadmin1 · Answer

Hi Chris, I don’t see the 'Move' under 'Action'. I only have 'Report abuse' and 'View as PDF'. Is there a way to grand me more privileges to do so? Regards, Mustafa Ahmed, Technical Support Engineer IV MBA - Technology Management, B.Sc. Engineering, LCNA, LCNS, EMCPA, EMCIE, EMCSA, EMCTA, EMCTAe Customer Service – BRS Remote NetWorker EMEA

christopher_ime · Answer

Mustafa, My response was directed to the author of the post as you won't be able to relocate it.  The owner is the only person that can relocate it out of his 'Discussions' space.

MikeCantr · Answer

Thanks for your help on getting to the correct forum

ble1 · Answer

If you wish to know about space and utilization, just run df (or filesys show space). For example:

Active Tier:

Resource           Size GiB   Used GiB   Avail GiB   Use%   Cleanable GiB

----------------   --------   --------   ---------   ----   -------------

/data: pre-comp           -   304312.6           -      -               -

/data: post-comp    64925.6    24411.8     40513.8    38%          1089.7

/ddvar                132.9        7.2       118.9     6%               -

----------------   --------   --------   ---------   ----   -------------

* Estimated based on last cleaning of 2013/11/03 13:33:32.

Obviously this is global and not per mtree. I would say it is wise to keep things under 80%.

When you do mtree list you are presented with pre-comp data... for example, here is combined view:

filesys show compression

From: 2013-10-30 21:00 To: 2013-11-06 21:00



                  Pre-Comp   Post-Comp   Global-Comp   Local-Comp      Total-Comp

                     (GiB)       (GiB)        Factor       Factor          Factor

                                                                    (Reduction %)

---------------   --------   ---------   -----------   ----------   -------------

Currently Used:   304356.9     24412.7             -            -    12.5x (92.0)

Written:*

Last 7 days      94035.3      4687.1          6.3x         3.2x    20.1x (95.0)

Last 24 hrs      14594.1       821.4          5.8x         3.1x    17.8x (94.4)

---------------   --------   ---------   -----------   ----------   -------------

mtree list

Name                     Pre-Comp (GiB)   Status

----------------------   --------------   ------

/data/col1/backup                   0.0   RW

/data/col1/server1             296044.5   RW

/data/col1/server2               7447.8   RW

----------------------   --------------   ------

I'm not sure why you wish to know post-comp for mtree, but I assume you wish to charge your customers what has been used and each is using their own mtree.

I do not have retention of 30 days, but rather 9 days (so I would most likely to my calculation based on weekly sums), but if I had I would use something like:

mtree show compression /data/col1/server1 last 30 days



From: 2013-10-07 22:00 To: 2013-11-06 21:00



                 Pre-Comp   Post-Comp   Global-Comp   Local-Comp      Total-Comp

                    (GiB)       (GiB)        Factor       Factor          Factor

                                                                   (Reduction %)

--------------   --------   ---------   -----------   ----------   -------------

Written:*

Last 30 days   408056.9     18750.9          6.7x         3.3x    21.8x (95.4)

Last 24 hrs     14273.3       791.4          5.8x         3.1x    18.0x (94.5)

--------------   --------   ---------   -----------   ----------   -------------

If using backup application, you can also try to derive some information from there (eg. mminfo -q ssid= -S will give you ss data domain dedup statistics which can be scripted further to get more details when and where needed).

MikeCantr · Answer

I would expect that the filesys show compression on the share (/data/col1) should collaborate the Used GiB value of 13351.3. However the l_comp reports 4.46TBs and I can sum the mtrees and get that value. So where does the 13351.3TB come from, this is what I am being told is the space currently used on Data Doamin. I should be able to determine what mtree is using how much.

Active Tier:

Resource Size GiB Used GiB Avail GiB Use% Cleanable GiB*

---------------- -------- -------- --------- ---- --------------

/data: pre-comp - 996469.2 - - -

/data: post-comp 43528.5 13351.3 30177.1 31% 904.5

/ddvar 132.9 8.3 117.8 7% -

---------------- -------- -------- --------- ---- --------------

* Estimated based on last cleaning of 2013/10/29 15:48:16.

filesys show compression /data/col1/

Total files: 95,037; bytes/storage_used: 352.4

Original Bytes: 1,589,059,090,280,291

Globally Compressed: 15,425,431,395,138

Locally Compressed: 4,460,758,109,764

Meta-data: 48,334,306,024

mtree list

Name Pre-Comp (GiB) Status

---------------------------- -------------- ------

/data/col1/SharePoint 2.7 RW

/data/col1/avamar-1376340593 988529.7 RW

/data/col1/backup 0.0 RW

/data/col1/biztalk 0.0 RW

/data/col1/oracle 91.1 RW

/data/col1/sql 7845.6 RW

---------------------------- -------------- ------

ble1 · Answer

I really don't know how to get that.  From what I have seen, mtree queries will give you data as per time period you query.  So, if you wish to compare it to df or filesys sh compression on mtree basis, you must do this based on retention and cleaning to get near the value shown. If someone from DD corner is lurking this space, they might join this discussion.

NetWorker

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