ONTAP Discussions

Enable space allocation command

IlirS
11,293 Views

Hello,

 

I tried to use unmap command for a vmfs datastore but I got the following error:

"Devices backing volume 556c77e1-b49cf970-f474-10604ba82a40 do not support UNMAP"

 

I read that space allocation should be enabled for the corresponding lun in order to use this command.

I just wanted to know what is the impact of "lun set space_alloc <lun_path> enable" command?

I mean, is it safe to run this command on a production lun when the lun is online and used by many users ?

 

BR,

Ilir

1 ACCEPTED SOLUTION

paul_stejskal
11,025 Views

Have you checked this KB? https://kb.netapp.com/app/answers/answer_view/a_id/1001100

 

It might depend on a few things. I'd make sure you're on 8.2.5P1 (or is P2 out?) and start there. If you can't get it after that let's get a support case open so we can review your system individually. There probably is something simple but I'd have to look at an ASUP to have a better idea.

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13 REPLIES 13

paul_stejskal
11,093 Views

7-mode or CDOT?

 

 

IlirS
11,086 Views

7-Mode

paul_stejskal
11,084 Views

The answer you seek is here: https://library.netapp.com/ecmdocs/ECMP1368845/html/GUID-AAA98EEC-0636-4EA8-96D4-FAFD95C94A29.html

 

Requires LUN offline according to that.

IlirS
11,081 Views

Actually I ran the command without taking the LUN offline and everything was ok.

Thank you for your support anyway.

 

BR,

Ilir

paul_stejskal
11,079 Views

I had a feeling it might work. It depends on the host OS probably how it handles it. But I think the documentation takes the "better safe than sorry" approach, which I share.

 

 

IlirS
10,936 Views

Hello Paul,

 

Even after enabling space allocation I'm still facing:

"Devices backing volume 556c77b8-458abb2e-73f2-10604ba82a40 do not support UNMAP"

 

The output of "esxcli storage core device vaai status get -d naa.60a9800038303246792b475348684159" command is showing the delete status as unsupported.

 

naa.60a9800038303246792b475348684159
VAAI Plugin Name: VMW_VAAIP_NETAPP
ATS Status: supported
Clone Status: supported
Zero Status: supported
Delete Status: unsupported

 

Do you have any idea ?

 

BR,

Ilir

paul_stejskal
11,026 Views

Have you checked this KB? https://kb.netapp.com/app/answers/answer_view/a_id/1001100

 

It might depend on a few things. I'd make sure you're on 8.2.5P1 (or is P2 out?) and start there. If you can't get it after that let's get a support case open so we can review your system individually. There probably is something simple but I'd have to look at an ASUP to have a better idea.

IlirS
10,851 Views

Hello Paul,

 

The strange thing is that I have done the UNMAP procedure successfully on other vmfs datastores that are residing on this same Netapp storage. So, I think that it is not operating system Data ONTAP related isn't it ?

 

Regarding opening the case it is not possible for the moment since the end-customer has not renewed the Netapp storage system support yet :((

 

BR,

Ilir

Fra
10,509 Views

Hello there, 

we have the exact same problem.

We run a CDOT Release 8.3.2P3 and we'd like to enable space reclamation on the 4 online production LUNs.

Vsphere 6.5 is already configured for Space Reclamation (PriorityLow: Deleted or unmapped blocks are reclaimed on the LUN at low priority), but as i understand, this is not working on the NetAPP side due to space-allocation disabled.

Does CDOT version support enabling space-allocation on online LUN?

 

Thank you

paul_stejskal
9,736 Views

8.3.2 does yes. The KB I linked above links https://kb.netapp.com/app/answers/answer_view/a_id/1003171. According to that you can.

Fra
9,601 Views

Hello Paul,
thanks for reply. Prior to made any modification on the system i just wanted to be sure about the results. I had read the KB, and i've also picked up the Clustered Data ONTAP® 8.3 SAN Administration Guide (update 8.3.2, that is exactly our version).
And now i'm a bit confused: on page 41, "Enabling space allocation for SCSI thinly provisioned LUNs", the documentation clearly says for step 1 to "Take the LUN offline".
I fear that enabling space-allocation on an online LUN, even for CDOT series, still seems to be uncharted territory.
Can you give us a feedback about that?
Thak you very much

paul_stejskal
9,561 Views

So, to avoid issues it's best to offline/online. If possible I would recommend a maintenance window to quickly flip the LUN.

aborzenkov
9,548 Views

Does not this option change information returned when host queries LUN properties? Which means for this option to have any effect host needs to rediscover LYN?

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