Doubts with cache


New Member
Jun 24, 2023
Hi guys, I'm new to ZFS. I am trying to understand some doubts using the ZFS filesystem on a baremetal proxmox server. Now, I've read a lot of related posts on the web (especially the proxmox guide which is great!) but I still have a question. I would have a proxmox configuration installed on ZFS RAID1 using 2x SSD (I will only store the operating system in these SSDs that we will call "A"). In addition, I will use other 2XSSDs (called "Bs") that will store a second ZFS with dedicated rpool for virtual machines. Let's also assume that I would plan to have CACHE and LOG on a separate nveme disk (only 1 SSD, no mirror).

My question is whether it makes more sense to use the nveme (for CACHE and LOG) attached to the first ("A") or the second ("B") ZFS.
What will be the pros and cons of each configuration?

Also, this is a third option: I will have the TrueNas instance installed on a proxmox VM. Passed to this VM there are 2xHD (in ZFS config.) where i can store data. It probably makes sense to use nvme here (for the cache log in the ZFS pool made by HD). But let's just say I wouldn't use them here because I don't have a big data load from my LAN to these hard drives...

Thank you so much for your help!!
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