Support for Multi-Path Plugins (MPP)
VirtuCache supports caching of datastores that are assigned VMware’s Native Multi-Path Plugin (NMP) only. We don’t support any other MPPs. This is not a cause for concern, since storage OEM MPPs are very rare these days, since almost all storage vendors use VMware’s default NMP MPP.
There is a new MPP called High Performance Plugin (HPP) starting in ESXi 6.7. It’s installed in ESXi 6.7 by default. We coexist with this MPP, no problem there. This plugin is for local high speed media like an NVME SSD. If the NVME SSD is using HPP, then VirtuCache will not be able to use the NVME SSD as cache media. You will have to unload/remove the claim rules which bind the HPP plugin to the SSD and if needed add/load claim rules to bind the NMP instead to the SSD. Also, it’s very rare that HPP plugin will be assigned to an SSD. It’s almost always that NMP plugin is assigned to the SSD.
You can find the MPPs installed in your ESXi host by running the command ‘esxcli storage core plugin list’