Add a Node to a 2 Node vSAN

[SSmalleyIT]

We have a 2 node vSAN with a physical witness.

We also have a single ESXi stand alone server with about 20 VMs running on it all on local storage.

All 3 units are near identical hardware and are vSAN Certified

We would like to add the single ESXi Standalone server to the vSAN cluster, however we're concerned about what will happen to the local data (vmdks and configs etc) when we import the 3rd Node?  Will the data remain and the VMs continue to run locally?  or is the data wiped and the disks rebalanced as part of the import process?

We have backups however I'd rather not have to restore TB's of data if it can be avoided.

Thanks in Advance

[TheBobkin · Accepted solution]

@SSmalleyIT This standalone host, I am assuming it has just VMFS configured on the disks whereas the others are using similar configuration for vSAN? If so then the process would be to add this node to the cluster, Storage vMotion the VM data off the VMFS to vsanDatastore, then once all the data is on this, remove the VMFS partitions and create vSAN Disk-Groups with the now-available disks.

To answer your question directly - No, adding a node to a vSAN cluster won't wipe any VMFS or other datastores and vSAN cannot claim a device unless there is no partitions on it (which VMFS or other file-system would have on them).

[SSmalleyIT]

@TheBobkin Perfect.  That's exactly what I wanted to hear.

Thanks