Currently, and only for testing purposes, I have a Zvol created on the RAIDZ2 in order to share a block device with iSCSI.
This isn't going to be particularly quick, as block storage such as VMFS demands rapid random I/O, which RAIDZ isn't very good at delivering - especially if it's also trying to fulfill requests from four other datasets against the same physical disks. Putting some of those 6x1T SSDs to work, on the other hand, should give you massively improved read results, and better writes (assuming they aren't QLC NAND such as a Samsung QVO)
Everything works almost as expected, the only thing I need to review is when I restart the vmware exsi server, the iSCSI configuration stops working, but this is a topic for another forum :)
You might be pleasantly surprised how many VMware nerds lurk around here. It's definitely not expected for a restart of the hypervisor to make the iSCSI extent unreachable - the other way around, certainly, but ESXi should rescan the bus and remount on boot.
I'm having fun with my homelab, it's true that I do not want to reinstall a VM every month, but If I lose anything, should not be a big problem. Also I have backups of the VMs so I'm not so reckless :P
To be honest; in this scenario, I don't believe you "need" an SLOG or sync writes. By your own admission, you're not storing data here that you can't afford to lose. It's a homelab, you're willing to rebuild, and you even have backups you can restore from. That shows an excellent understanding of your own personal risk tolerance; so leaving
sync=standard set may just be the best option here, rather than picking up an SLOG device at a premium.
If you do not have [in-flight PLP] (or equivalent, such as Optane), then you do not have a SLOG which can guarantee sync writes.
Well, you probably still do - it's just only marginally better than putting said sync writes on the in-pool ZIL itself. Unless the device is lying about sync writes (glares at his old OCZ Vertex 2) then it's still the same "safe, but slow" as writing to your pool devices.
There's a list of SSD's over in the Resources section, I believe.
Not yet; maybe I should work on that.
I'd like to take a few minutes to talk about SLOG devices and what makes good ones versus bad ones. I have no doubt that this will be a controversial topic since this is not well understood by many people. In short, there's 3 things that you need for a "great" SLOG: 1. Fast throughput 2...
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