I’ve been a user of Unraid since 2012, when I had to find a solution to my home storage after Windows Home Server was abandoned by Microsoft. Unraid has been very good for me, and the introduction of a Docker engine with Unraid 6 was very welcome. That said, I’ve recently encountered issues with bitrot, and the fact that unraid can’t use ZFS as the disk format annoys me. LimeTech claim that their parity check process should detect bitrot – however, something doesn’t seem to be working, as using using the Dynamix File Integrity plugin i can see it happening. In any case, knowing it’s happened isnt the same as being able to correct it, which just isn’t possible on Unraid without using BTRFS but many people simply don’t trust BTRFS, and besides, I fancy a change. So – over to VMWare EXSi and ZFS on Napp-It.
This blog post describes the hardware i needed.
The HP Gen8 Microserver is certified for use with VMWare and you can even install it to an internal USB or MicroSD card. In my case, I want a RAIDZ array of 3 x 4TB drives, plus two or more SSDs for VM and Docker hosts.
For ZFS to work properly it needs access to the underlying host controller, not a virtualised verison. VMWare is capable of direct device passthrough, but only on processors which support VT-d. Additionally, if I’m running a VM (the Napp-IT guest) on a drive on the storage controller, I can’t pass that same storage controller through to the guest.
When i bought my microserver, i got the base model, and with cashback i think it cost me £120. But the base has a Celeron G1060 and although this has the VT-x extensions, it doesn’t support VT-d.
The B120i controller in the Gen8 has 2 6GBs SATA channels, and 2 3GBs. I wanted to ensure that all 4 drive bays ran at 6GBs, plus have 2 6GBs channels for my host SSDs.
My shopping list was therefore:
- a new processor supporting VT-d. I used the chart maintained by users of the homeservershow forum to find a suitable processor for sale on eBay. I ordered an E3-1260L from China. Estimated delivery – a few weeks.
- Some thermal paste
- A second storage controller. I went for the IBM ServeRaid M1015 as it can be flashed to an LSI9211-81 in IT mode (meaning ZFS has direct access to the disks, without the controller being “smart” or “doing RAID” in the middle). See this post for instructions.
- a Mini SAS (SFF-8087) to SATA cable, again from eBay.
some things i already had:
- a molex splitter (I already had this)
- a molex to two SATA HDD power splitter