1, the number of cluster nodes: 3-64 Host (production environment at least 4 nodes, 5.5 version support 32 nodes, 6.0 version support 64 nodes), configure the Gigabit network card, host specifications should meet the Vsan compatibility requirements.
2, each host needs to configure the disk group, the number of disk groups per host at least 1, a maximum of 5.
3, the disk group consists of two parts: the cache layer + storage layer, the cache layer must use a flash device (generally SSD), storage layer can choose all-flash device (SSD) or full-mechanical hard disk (HDD).
4. Each disk group must be configured with a minimum of 2 disks (cache layer 1 + storage layer 1 blocks), up to 8 disks ( cache layer 1 blocks + storage Layer 7 blocks), the cache layer can only have 1 disks.
5, storage devices (SSD+HDD) need to be evenly distributed to each host, otherwise it will affect the number of virtual machines that the cluster can support.
6, Storage layer configuration multi-block small capacity disk than the configuration of a few large capacity disk performance is better.
7, in mixed mode, the cache of 70% is used as a hot block read cache, 30% for write cache; All-flash mode, the cache is all used as the write cache, because the data disk read performance is high enough.
8, SSD capacity is recommended to be configured for HDD capacity of more than 10%, the maximum support 600G as a cache use.
9, the same cluster does not support the coexistence of mixed mode and all-flash mode.
10, more disk group performance better, can also reduce the fault domain.
VMware Vsan Design Rules