Despite identical configuration, two clusters show different aggregate capacity
Issue
- Two different clusters, both running ONTAP >= 9.12.1, report a different usable aggregate size.
- Both aggregates are configured identically (same raid-level, same drive-count, same drive- / partition-size, etc.
- The size of the aggregates is short below 30TB.
- The difference is roughly 5%:
cluster1::*> aggr show -fields size,diskcount -root false
aggregate diskcount size
----------------------- --------- -------
aggr_data01 22 26.64TB
cluster2::> aggr show -fields size,diskcount -root false
aggregate diskcount size
----------------------- --------- -------
aggr_data02 22 28.12TB
Note: This example is from a Metrocluster which does reserve 5% aggregate Snapshot reserve by default on top of the hidden WAFL reserve.
- Cluster with smaller aggregate was upgraded to >=9.12.1.
- Cluster with larger agrgegate was fresh installed on >=9.12.1.