Specifically as this is a UK website (!) and to expand the facts further, Lenovo offer following HCI/SDS in UK:
Nutanix as a Lenovo part number (3 models today), supplied from factory pre integrated using Lenovo hardware
Then as meet in channel today its:
Pivot3 as a meet in the channel with Lenovo UK Distributor Arrow
Simplivity as a Meet in the channel with Lenovo UK Distributor Arrow
Atlantis as a meet in the channel, primarily with Lenovo UK Distributor Azlan/TecData
DataCore as a meet in the channel with UK Distributor Exertis (existing DataCore Distributor)
Cloudian - as meet in channel, sold through resellers with Lenovo Hardware
StorMagic - meet in channel, sold through resellers with Lenovo Hardware
Reference Architectures & Bill of Materials exist for all the above.
There's also VMware virtual SAN..of course. But no EVO;RAIL....
On the more traditional storage side, Lenovo OEM the IBM v3700 and v7000 storwize products, as well as having their own S Series products, S2200 and S3200. And there was an announcement and blog in February regards IBM Spectrum Technology Software, in next-gen storage.
Heres the link: http://blog.lenovo.com/en/blog/lenovo-to-use-ibm-spectrum-software-technology-in-next-gen-storage/
Being an open and flexible hardware vendor has its benefits in the HCI/SDS marketplace.