Before you install or upgrade NSX, consider your network configuration and resources. You can install one NSX Manager per vCenter Server, one instance of Guest Introspection per ESXi™ host, and multiple NSX Edge instances per datacenter.
*As a general guideline, if your NSX managed environment contains more than 256 hypervisors, we recommend increasing NSX Manager resources to 8 vCPU and 24 GB of RAM. For specific sizing details contact VMware support.
For information about increasing the memory and vCPU allocation for your virtual appliances, see Allocate Memory Resources, and Change the Number of Virtual CPUs in vSphere Virtual Machine Administration.
For the latest interoperability information, see the Product Interoperability Matrixes at http://partnerweb.vmware.com/comp_guide/sim/interop_matrix.php.
For recommended versions of NSX, vCenter Server, and ESXi, see the release notes at https://www.vmware.com/support/pubs/nsx_pubs.html, and https://kb.vmware.com/kb/2144295.
Note that for an NSX Manager to participate in a cross-vCenter NSX deployment the following conditions are required:
To manage all NSX Managers in a cross-vCenter NSX deployment from a single vSphere Web Client, you must connect your vCenter Servers in Enhanced Linked Mode. See Using Enhanced Linked Mode in vCenter Server and Host Management .
To check the compatibility of partner solutions with NSX, see the VMware Compatibility Guide for Networking and Security at http://www.vmware.com/resources/compatibility/search.php?deviceCategory=security.