1) A correction
to this post from July 2014: Volume
and Qtrees Quotas in Clustered ONTAP: Tracking Quota
To enable tracking quotas for all Qtrees in a
volume (you do not need to create a tracking rule for every qtree), it is
simply ::>
volume
quota policy rule create -vserver SVMNAME -policy-name POLICYNAME -volume
VOLUMENAME -type tree -target "" -threshold "-"
volume
quota on -vserver SVMNAME -volume VOLUMENAME
{Where POLICYNAME
is the currently active Quota Policy on the SVM, with default policy being
default}
When the volume quota has finished initializing (quota show -vserver SVMNAME
-volume VOLUMENAME), to get a report for ‘Disk Used’ and ‘Files Used’
for all Qtrees in that volume ::>
volume
quota report -vserver SVMNAME -volume VOLUMENAME
2) Quotas and
Volume Autosize Considerations
From TR 3505 NetApp
Deduplication:
6.4.1 QUOTAS
For deduplicated
files, the logical
(undeduplicated) size is charged against the quotas. There are several
advantages to this scheme as opposed to charging quotas based on the physical
(deduplicated) size of the file:
i) This is in line
with the general design principle of making deduplication transparent to the
end user.
ii) It is easier
for system administrators to manage quotas. They can maintain a single quota
policy across all volumes, whether or not deduplication is enabled on it.
iii) There are no
out-of-space failures when data is being sent using SnapMirror from a volume
with deduplication enabled to a destination volume that has deduplication
disabled.
To understand the effect of seeing the logical
(undeduplicated) size when using Qtree quotas, here are 3 examples. In each
example, we have a 1000MB thin-provisioned volume (space guarantee none), with
no snapshots, dedupe is enabled on the volume, and Qtree tracking quotas are enabled.
We use the same 210 MB folder multiple times (so it de-dupes very well!) The
Storage Virtual Machine and AD Machine Account is called cifsv1.
2.1) Example 1:
4 x the same 210MB folder (~840MB) in one Qtree
Image: Example 1 Data
Layout
DOS Commands to Map Drives:
net
use V: \\cifsv1\vol1
net
use Q: \\cifsv1\vol1\qtree1
net
use R: \\cifsv1\vol1\qtree2
Image: Displayed
via a Windows Client for Example 1
2.2) Example 2:
The same 210MB folder (~840MB) in 3 Qtrees and the root of the Volume
Image: Example 2 Data
Layout
DOS Commands to Map Drives:
net
use V: \\cifsv1\vol2
net
use Q: \\cifsv1\vol2\qtree2
Image: Displayed
via a Windows Client for Example 2
2.3) Example 3:
5 x the same 210MB Folder (~1050MB) in one Qtree
Image: Example 3
Data Layout
DOS Commands to Map Drives:
net
use V: \\cifsv1\vol3
net
use Q: \\cifsv1\vol3\qtree3
Image: Displayed
via a Windows Client for Example 3
3) Volume
Autosize Considerations
Generally, when dedupe and Qtree quotas are in effect,
the free space the end user will see is:
End User Free
Space = {Volume Size} - {Logical (Un-deduped) Data Size in the Qtree}
- or, if the actual (including dedupe) data size in the
volume is larger than the logical data size in the Qtree -
End User Free
Space = {Volume Size} - {Actual (Including Dedupe) Data Size in the volume}
We see in example 1 above, the volume share shows the
actual free space available in the volume as 797 MB, but the qtree share shows
a much smaller free space value of 150 MB. This has implications regards
setting volume autosize, in essence:
Volume AutoSize Size
Setting = ( {Volume Size} - {Logical (Un-deduped) Data Size in the
Largest Qtree} + {Actual (Deduped) Data Size in the Volume} )* {Percentage
Autogrow Threshold}
- or, if the actual
(including dedupe) data size in the Volume is larger than the logical data size
in the largest Qtree, we get the typical formula -
Volume AutoSize
Size Setting = {Volume Size} * {Percentage Autogrow Threshold}
In example 1, even though the volume is only 203 MB used
out of 1000 MB, if the user is accessing Qtree1, and tries to add more than 150
MB, this will fail (even though there is 797 MB free space in the volume), and
the autosize will not have triggered if it were set at 850MB.
Example 1: AutoSize
Size Setting = ( 1000 - 850 + 203 ) * 0.85 ~= 300 MB
Example 2: AutoSize
Size Setting = 1000 * 0.85 = 850 MB
Note: Interestingly,
in Example 3, you might expect to see negative user space when we have 1050 MB logical
data in a Qtree in a 1000 MB volume, but that doesn’t happen, the Windows
client then shows the deduped data size in the volume!
4) Final
Comment
If your end-user is saying his share is full and he needs
more space, but the volume is far from being full, nor is the aggregate, and
volume autosize has not kicked in as expected, suspect dedupe and quotas!
Thanks for the post we faced similar issue , your explanation makes sense
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