ONTAP Discussions

Volume containing LUN best practices

Kiko
1,306 Views

Hi!

I have a question about the properties to assign to a volume in an AFF array that serves a LUN via FC.
Basically the question is whether in this scenario enabling autogrow makes sense if what you are serving is a LUN and if space reservation for snapshots should be enabled or not.

On the other hand, snapshot autodelete, I imagine that it would be recommended to enable it.

Thank you so much

1 ACCEPTED SOLUTION

Ontapforrum
1,270 Views

Basic guidelines:
Each LUN in a separate volume
Space Guarantee:None
Autogrow:Enabled (If snapshots are enabled, it depends what is it (LUN) used for -SQL/EXCH/ORCL/Databases etc, if snapshots are managed by ONTAP. If the host application manages 'data-recovery', at the host-side, and netapp snaps aren't needed, then disable snapshots)

 

Please Note: If a space-reserved LUN is created in a none-guaranteed volume, the LUN behaves the same as a non-space-reserved LUN, so basically it has no effect. Hence, it makes sense to disable space-reservation and keep volume & LUN THIN (unless you are asked to make it (vol/lun) thick b'cos of the requirements from your organization).

 

Following Kbs worth reading:
https://kb.netapp.com/onprem/ontap/os/FAQ%3A_Over_Provisioning_aka_Thin_Provisioning_in_ONTAP
https://kb.netapp.com/onprem/ontap/os/LUN_has_been_brought_offline_with_space-allocation_disabled
https://docs.netapp.com/us-en/ontap/san-admin/automatic-host-side-space-management-concept.html

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Ontapforrum
1,271 Views

Basic guidelines:
Each LUN in a separate volume
Space Guarantee:None
Autogrow:Enabled (If snapshots are enabled, it depends what is it (LUN) used for -SQL/EXCH/ORCL/Databases etc, if snapshots are managed by ONTAP. If the host application manages 'data-recovery', at the host-side, and netapp snaps aren't needed, then disable snapshots)

 

Please Note: If a space-reserved LUN is created in a none-guaranteed volume, the LUN behaves the same as a non-space-reserved LUN, so basically it has no effect. Hence, it makes sense to disable space-reservation and keep volume & LUN THIN (unless you are asked to make it (vol/lun) thick b'cos of the requirements from your organization).

 

Following Kbs worth reading:
https://kb.netapp.com/onprem/ontap/os/FAQ%3A_Over_Provisioning_aka_Thin_Provisioning_in_ONTAP
https://kb.netapp.com/onprem/ontap/os/LUN_has_been_brought_offline_with_space-allocation_disabled
https://docs.netapp.com/us-en/ontap/san-admin/automatic-host-side-space-management-concept.html

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