I have a HUS130 with an existing RAID5(3D+1P) RAID group that I would like to grow to a RAID5(4D+1P), but I cannot find any mechanism for doing this in SNM2. Can this be done?
Yes, this can be done. Locate the Expand RG option from Groups > Volumes > RAID Groups.
The RAID group that I want to expand is not listed under the RAID Groups tab because it is actually part of a DP Pool. So I guess it is considered a DP RAID Group. There are six DP RAID Groups that appear on this list, divided into three tiers. Below is a screenshot of the DP Pool.
I just want to enlarge DP RAID Group 070 by one more disk. Selecting 070 and clicking the "Add Pool Capacity" button gives me the following error:
But the disk that I want to add is installed and shows a "Mounted" status. Because this particular RAID Group is part of a DP Pool, does that mean it cannot be expanded?
Oh in the case of a DP pool, you can't expand individual RGs. You have to expand the pool with an entire additional RG.
Now that I understand that you cannot expand a RG that is part of a DP Pool, can I drop this RG from the DP Pool. Currently it is the only RG in Tier1 of my DP Pool.
If so I can then expand it when it is a regular RG.
Doing some reading, am I understanding correctly that when I "Shrink Pool Capacity" I am actually dropping a RG from the Pool? Also is RAID5(4D+1P) configuration supported for a RG? The whole point of all of this is to expand the SSD RG from RAID5(3D+1P) to RAID5(4D+1P).
Your understanding is correct. Shrinking Pool Capacity is remove one or more RGs from the pool. Data that resides on that RG will be migrated to other RGs.
RAID5 4+1 is one of the available RAID types on the HUS family.
For completeness I wanted to state what I did. From the Groups > Volumes > DP Pool page I selected the 070 RG and clicked the "Shrink Pool Capacity" button. Data was moved off the RG and then it was dropped as Tier1 while the other tiers were promoted (Tier2 became Tier1 and Tier3 became Tier2). Next I clicked the "Add Pool Capacity" button and recreated RG 070 as RAID5(4D+1P) and it was assigned Tier1 and the other tiers were demoted again.
So the process is complete and thank you again.
Hi Evelio - thanks for sharing the end results!
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