New Proxmox 4.2 Installation - suggestions for hardware size / combination

michaeljk

Renowned Member
Oct 7, 2009
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Hi,

we are currently using a Proxmox 3.4 cluster and want to upgrade to new hardware with a fresh Proxmox 4.2 installation. Planned hardware:

Dell R730XD with 2x Hexa-Core CPUs
8x 2TB Enterprise SATA 7.200 HDDs (ZFS RAID10)

Mostly mixed Linux VMs (LAMP, Database- / Mailserver, Fileserver, Proxy-Server, ...). We have the following options:

- RAM from 128 GB up to 384 GB
- Up to 4 additional SATA ports for SSD (Samsung SM863 or Intel DC S3500)

I'm a little bit confused which hardware combination would work best with our setup:

- Mirrored SLOG? Which size? Dedicated SSD-Device or partitioned for SLOG / L2ARC?
- L2ARC needed / recommended for the given RAM-size? If yes, which size and would 1 SSD-device work?
- What to use as Root-device for the Proxmox-Installation / OS? Dedicated, single SSD? Or will a ZFS root (mirrored) also be stable enough?
- We would like to use most of the RAM for the installed VMs but also ensure that ZFS performance will not suffer. I guess that L2ARC shouldn't be too big as it also uses RAM. But which size of SLOG / L2ARC is recommended for 128 / 256 / 384 GB RAM? Which size should be configured for ARC in general?

Michael