Storage Pools and aggregates

[francisjkim]

8.3 docs on "Physical Storage" only refers to Flash Pools when talking about using Storage Pools on SSDs.  Is there some reason the Storage Pool allocations can't/shouldn't be used to create all-SSD aggregates as well?  Nos supported?  Not BP?

[SeanHatfield · Accepted solution]

HI Francis,

Storage pools partition the SSDs differently.  In a pure SSD aggregate they are either unpartitioned, or root/data partitioned if the platform was initialized with ADP.  Storage Pool's partition them into 4 slices so you can apply cache to more aggregates with fewer SSDs.

https://library.netapp.com/ecmdocs/ECMP1636022/html/GUID-8284CB30-5BC5-4D10-B0AA-AA8F8DAA752E.html

[francisjkim]

Sean,

My core question is, how disk-like are the four SSD partitions that get created when you create Storage Pools?  Can I make a pure SSD aggregate out of them, or is their use limited to adding cache space to Flash Pools?

What I wanted to explore was to see if we can apply the parity amortization advantage of Storage Pools beyond Flash Pools.

[SeanHatfield]

I think what you're looking for is ADPv2.  There each SSD gets 2 data slices and a root slice.  The data slices become 2 data aggregates.  Each controller gets a data aggregate and half the root slices.

The storage pools are only intended for cache.  but now that you've piqued my interest some vsims will be sacrificed exploring that question.

[SeanHatfield]

Curiosity satisfied.  Once SSDs are placed into a storage pool they are prevented from being used in an aggregate.

Here I've made a storage pool called "cache1", which appears as the container name in the disk list:

crshtst1::storage pool*> disk show
                     Usable           Disk    Container   Container   
Disk                   Size Shelf Bay Type    Type        Name      Owner
---------------- ---------- ----- --- ------- ----------- --------- --------
VMw-1.1              7.10GB     -   0 VMDISK  aggregate   aggr0     crshtst1-01
VMw-1.2              7.10GB     -   1 VMDISK  aggregate   aggr0     crshtst1-01
VMw-1.3              7.10GB     -   2 VMDISK  aggregate   aggr0     crshtst1-01
VMw-1.4              7.10GB     -   3 VMDISK  spare       Pool0     crshtst1-01
VMw-1.5              7.10GB     -   4 VMDISK  spare       Pool0     crshtst1-01
VMw-1.6              7.10GB     -   5 VMDISK  spare       Pool0     crshtst1-01
VMw-1.7              7.10GB     -   6 VMDISK  spare       Pool0     crshtst1-01
VMw-1.8              7.10GB     -   8 VMDISK  spare       Pool0     crshtst1-01
VMw-1.9              7.10GB     -   9 VMDISK  spare       Pool0     crshtst1-01
VMw-1.10             7.10GB     -  10 VMDISK  spare       Pool0     crshtst1-01
VMw-1.11             7.10GB     -  11 VMDISK  spare       Pool0     crshtst1-01
VMw-1.12             7.10GB     -  12 VMDISK  spare       Pool0     crshtst1-01
VMw-1.13             7.10GB     -  13 VMDISK  spare       Pool0     crshtst1-01
VMw-1.14             7.10GB     -  14 VMDISK  spare       Pool0     crshtst1-01
VMw-1.15             7.10GB     -  15 VMDISK  spare       Pool0     crshtst1-01
VMw-1.16             3.55GB     -   0 SSD     shared      cache1    crshtst1-01
VMw-1.17             3.55GB     -   1 SSD     shared      cache1    crshtst1-01
VMw-1.18             3.55GB     -   2 SSD     shared      cache1    crshtst1-01
VMw-1.19             3.55GB     -   3 SSD     shared      cache1    crshtst1-01
VMw-1.20             3.55GB     -   4 SSD     shared      cache1    crshtst1-01
VMw-1.21             3.55GB     -   5 SSD     spare       Pool0     crshtst1-01
21 entries were displayed.

Now the usual aggr creation method fails, because I don't have enough spare SSD left:

crshtst1::storage pool*> aggr create -aggregate ssd1 -diskcount 5 -disktype ssD           
[Job 21] Job is queued: Create ssd1.                                               

Error: command failed: [Job 21] Job failed: Failed to create aggregate "ssd1"
       on "crshtst1-01". Reason: 5 disks needed from one pool, but not enough
       matching disks are available in either pool. 

I can see the partitions though:

crshtst1::storage disk partition*> show
                          Usable  Container     Container
Partition                 Size    Type          Name              Owner
------------------------- ------- ------------- ----------------- -----------------
VMw-1.16.P1               895.5MB spare         Pool0             crshtst1-01
VMw-1.16.P2               895.5MB spare         Pool0             crshtst1-01
VMw-1.16.P3               895.5MB spare         Pool0             crshtst1-01
VMw-1.16.P4               895.5MB spare         Pool0             crshtst1-01
VMw-1.17.P1               895.5MB spare         Pool0             crshtst1-01
VMw-1.17.P2               895.5MB spare         Pool0             crshtst1-01
VMw-1.17.P3               895.5MB spare         Pool0             crshtst1-01
VMw-1.17.P4               895.5MB spare         Pool0             crshtst1-01
VMw-1.18.P1               895.5MB spare         Pool0             crshtst1-01
VMw-1.18.P2               895.5MB spare         Pool0             crshtst1-01
VMw-1.18.P3               895.5MB spare         Pool0             crshtst1-01
VMw-1.18.P4               895.5MB spare         Pool0             crshtst1-01
VMw-1.19.P1               895.5MB spare         Pool0             crshtst1-01
VMw-1.19.P2               895.5MB spare         Pool0             crshtst1-01
VMw-1.19.P3               895.5MB spare         Pool0             crshtst1-01
VMw-1.19.P4               895.5MB spare         Pool0             crshtst1-01
VMw-1.20.P1               895.5MB spare         Pool0             crshtst1-01
VMw-1.20.P2               895.5MB spare         Pool0             crshtst1-01
VMw-1.20.P3               895.5MB spare         Pool0             crshtst1-01
VMw-1.20.P4               895.5MB spare         Pool0             crshtst1-01
20 entries were displayed.

But I still can't use them to create an aggregate

crshtst1::storage disk partition*> aggr create -aggregate test1 -partitionlist VMw-1.16.P1,VMw-1.17.P1,VMw-1.18.P1,VMw-1.19.P1,VMw-1.20.P1
[Job 22] Job is queued: Create test1.                                          

Error: command failed: [Job 22] Job failed: Failed to create aggregate "test1"
       on "crshtst1-01". Reason: Disk "VMw-1.16.P1" is part of a storage pool.
       Please use the 'aggregate add' command with the '-storage-pool' option
       to add capacity from a storage pool to an aggregate.