We have a VSAN 6.5 with 9 nodes which is currently at 69% storage utilization and 204TB, with +320 VMs.
Future growth is a bit difficult to predict.
According to VMware sizing guidelines;
Keep at least 30 percent unused space to prevent Virtual SAN from rebalancing the storage load.
Virtual SAN rebalances the components across the cluster whenever the consumption on a single capacity device reaches 80 percent or more.
The rebalance operation might impact the performance of applications. To avoid these issues, keep storage consumption to less than 70 percent.
Could anyone shed any light on how these rebalancing storage load operations would affect the VMs from an availability and performance standpoint?
Would it look like the VM is unavailable or just not responding? Would it affect all VMs or just the subset of VMs on the host >80% load?
At what additional risk is the VSAN when storage load is at 70% vs 80% used space?
Looking for advice and experience.
regards
Gaute