different Hard Disk size adding in existing vSAN Group ,

[bilalahmed]

Hi Expert ,

my question is that , vSAN 4 node already running with 2 disk group each 1*800 GB ( Write Intensive) SSD and 4*1.6 TB (Read Intensive) SATA SSD .Now i want to increase the storage space but unfortunately 1.6 TB is not available , can i add  1*1.92 TB in existing each Disk Groups of all 4 Node.

Please also suggest any VMware Links.

Thank you

[NicolasAlauzet]

Hi there, yes you can add disks with different capacity to a vsan cluster. Just a recomendation from my side would be to keep the same in all the hosts so in the future going to maitenance is not that painfull.

EDIT= About vSAN Planning and Deployment

[bilalahmed]

Hi NicolasAlauzet

Yes , off course i will add the same size of Hard Disk on All 4 Nodes Disk Groups , i just want to clarify this ,  can i get any vmware article on that .

Thanks

[TheBobkin]

Hello Bilal,

Any documentation relating to this will state that we advise a homogenous configuration across the cluster, however you may also note that most of these resources will state something to the effect of 'per-host homogeneity' as this is the important part (e.g. don't have 3 nodes with 10TB capacity each and 4th node with 30TB capacity) - if you are adding additional disks of larger size to each Disk-Group, this is fine and completely supported. The difference in disks size you noted are not massively varying, a performance impact may be noticeable if for instance you were adding disks twice the size of the current ones as these disks would be storing twice as much data and thus serving twice as many IO operations, however do ensure that the devices you are adding are equal or better in performance spec and type as the ones in use.

"vSAN works best on hosts with uniform configurations"

Design Considerations for a vSAN Cluster

Relatively old but support statement remains the same:

Support for Non-Uniform/Heterogeneous VSAN clusters? Yes! - Virtual Blocks