4.2 install on Debian Jessie with ZFS

[MimCom]

Hit a wall with the 4.2 native ZFS installer, so I did a minimal Jessie (8.5) install to an mSATA SSD. Built a ZFS RAID10, added a ZIL and L2ARC on a an NVMe SSD. Not sure what my next steps are with regard to installing Proxmox -- wiki recipes all seem to reference LVM, which seems rather silly to layer on top of ZFS. Do I divide the zpool into data, root, and swap somehow? If I start over with the native Proxmox installer will it be able to recognize the existing zpool and install to that?

thank you~

 

[dietmar]

regarding zfs, you can simply create a zfs subvolume and use it with proxmox.

 

[MimCom]

Thank you, Dietmar. So create subvolumes for data, root, and swap?

 

[dietmar]

Thank you, Dietmar. So create subvolumes for data, root, and swap?

You wrote that you already installed the system, so I guess you have root and swap already.

 

[MimCom]

Yes, everything is on the mSATA SSD (where the Debian installer put them.) Still wrapping my head around the concepts here, so bear with me.

From what I can find, subvolume seems to be a btrfs concept. I'm guessing 'zfs create' as opposed to 'mkdir' here. Also, am I better off putting swap on zfs, or allocating separate swap partitions on multiple drives like we used to do?

I believe I have answered my other question: It seems neither the Proxmox installer nor the Debian installer recognize the existing zpool, and the Proxmox installer does not seem able to complete an install on the new zpool it creates.

 

[MimCom]

Come to think of it, swap on an SSD might be a good idea -- or perhaps something like swapspace would a better plan?

 

[LnxBil]

Be advised that there a stability problems concerning swap on ZFS with heavy I/O load. Search the forums for that. I had several crashes and migrated to dedicated disks for OS and swap (small 2x 146 GB) and a dedicated ZFS pool for proxmox.

I'd suggest to use zram for swap in the first place. This is the way to go on newer systems and hopefully, this will be integrated into Debian and therefore Proxmox directly.

 

[MimCom]

Thanks -- I went ahead and built a small swap partition on the SSD after reading up a bit. Putting swap on ZFS seemed like it would just add more layers to what should be an infrequently-used subsystem. So you are running / on a separate drive and just the VM hive on ZFS?

I've been watching zram for awhile, it seems like a good architectural move.

 

[LnxBil]

Yes, the base system with swap on LVM on a local raid 1 SAS 10k drive (included in most server systems). This leaves space for crashdump aswell.

For my ZFS pool I have two MSA60 attached with a SAS2008-based controller.