How to use the additional NVM SSDs

[Vertex]

I plan to install TrueNAS on a 6 bay QNAP NAS which got 2x500 GB SSDs for caching. The simplest way would be to use one of them as boot drive for TrueNAS and the other one as SSD cache. But I feel bad to waste the whole 500GB for a boot drive. What would be the smartest an common way to use the two SSDs for TrueNAS ? I have to say, it is a small bussiness environment, so aim to a solid and reliable solution.

Thank you for your help in advance.

 

[ChrisRJ]

The only supported way is to use the boot disk in its entirety as the boot disk. There are ways to manually partition it. But those are advanced, unsupported, and you run the risk of loosing data.

As to caching, if you have at least 64 GB you can use the other SSD as L2ARC.

Please have a look at the first couple of links in the "Recommended readings" in my signature. You will need to have a certain level of knowledge about ZFS and TrueNAS to avoid issues. ZFS has some special properties and same are let's counter-intuitive.

Edit: The use of the other SSD as an SLOG device would not be a good idea. In general "caching" in ZFS is very different from other file systems.

 

[Vertex]

Edit: The use of the other SSD as an SLOG device would not be a good idea. In general "caching" in ZFS is very different from other file systems.

I have already decided not to use SLOG, as far as I know would not make sense for my use case and it would just add another layer of complexity.
I have seen people manually partitioning their SSDs in a kind of mirrored configuration and I was not sure if this is an good idea. You confirm my concerns. I will go for a conventional configuration as you recommend. I do not have any experience with ZFS yet, but I am very keen on its features as snapshots and very flexible encryption, which is very handy.

At the moment I dive into any helpful sources to get a deeper understanding about ZFS, thank you very much for your hints and the helpful links.