You can add an ESXi host to a running vSAN cluster without disrupting any ongoing operations. The host's resources become associated with the cluster.
Verify that the resources, including drivers, firmware, and storage I/O controllers, are listed in the VMware Compatibility Guide at http://www.vmware.com/resources/compatibility/search.php.
VMware recommends creating uniformly configured hosts in the vSAN cluster, so you have an even distribution of components and objects across devices in the cluster. However, there might be situations where the cluster becomes unevenly balanced, particularly during maintenance or if you overcommit the capacity of the vSAN datastore with excessive virtual machine deployments.
- Navigate to the vSAN cluster in the vSphere Web Client.
- Right-click the cluster and select Add Host.
- Enter the host name or IP address, and click Next.
- Enter the user name and password associated with the host, and click Next.
- View the summary information and click Next.
- Assign a license key and click Next.
- (Optional) Enable lockdown mode to prevent remote users from logging directly in to the host.
You can configure this option later by editing the Security Profile in host settings.
- Select what to do with the host’s virtual machines and resource pools.
Put this host’s virtual machines in the cluster’s root resource pool
vCenter Server removes all existing resource pools of the host. The virtual machines in the host’s hierarchy are all attached to the root. Share allocations are relative to a resource pool, so you might have to change a virtual machine’s shares. Making this change destroys the resource pool hierarchy.
Create a resource pool for this host’s virtual machines and resource pools
vCenter Server creates a top-level resource pool that becomes a direct child of the cluster and adds all children of the host to that new resource pool. You can type a name for that new top-level resource pool. The default is Grafted from <host_name>.
- Review the settings and click Finish.
The host is added to the cluster.
For more information about vSAN cluster configuration and fixing problems, see vSAN Cluster Configuration Issues.