From ONTAP Select document and TR-4517, I have following understanding:
- General guidance of single–RAID group/single-LUN from underlying server DAS
- LUN size limit by hypervisor extent limitation (64TB)
- Create multiple equal-sized LUNs if limit reached, then provision the vSphere datastore using all attached LUNs
- ONTAP Select receives no performance benefits by increasing the number of LUNs within the RAID group. Adding additional LUNs should only be done to bypass hypervisor file system limitations.
- After ONTAP select VM is deployed and root disks provisioned, the underlying attached storage is breaks up the into even number set of equal-sized virtual disks, each not exceeding 8TB
- Similar to creating multiple LUNs, ONTAP Select receives no performance benefits by increasing the number of virtual disks used by the system.
- When the second RAID group is added (server DAS), a second LUN must be provisioned and should be added as a new extent to the existing datastore.
- NetApp recommends that newly attached storage be added to the existing datastore as a new extent, rather than configured as a second datastore on the system.
- the newly assigned storage should be split into an even number set of equal-sized virtual disks, not exceeding 8TB
- Currently, the ONTAP Deploy tool does not support the workflow of adding space to a Select node, so this process must be done using the native vSphere tooling.
- For four node ONTAP select cluster, all aggregate is RAID 0 and must be mirrored.
- maximum aggregate size is 100TiB
- maximun volume size is 60TiB
My question are:
- Can I create aggreate with more than 2 disks (X = even mumber)?
- this means X/2 number of raidgroup in each plex? (one raidgroup per disk)
- Will there be any performance penalty?
- If I increased the underlying datastore size and created more virtual disk, can I add the disks to the existing aggregate?
- what are the consideration?
