1) Not sure which model of HP server you are looking at but here are a few notes of consideration:
- From what I've seen the embedded P420i has a better queue depth than the H220 (both on the HCL) and the latest HP ready nodes use the 420i in both medium and high workload ready nodes. See the community queue depth sheet by William Lam here: https://docs.google.com/spreadsheets/d/1FHnGAHdQdCbmNJMyze-bmpTZ3cMjKrwLtda1Ry32bAQ/edit#gid=0
- If you order the HP server you will be tempted to do so without the cache (since you don't need the controller cache as you would disable it anyway). Don't do this. If you have zero cache on the controller, you will be limited to creating 3 RAID0 disks. You need the cache on board and you disable it, this will enable you to provision all of your disks as RAID0 (the way you get around pass-thru with RAID controllers)
- To expand your disk group by adding disks or to create a new disk group by adding disks online, you'll need to use the Array Configuration Utility command line from HP and configure groups remotely. If anyone else can verify if there is a GUI or another way to do it from the host, that would be great, but from what we've seen so far you need the ACU CLI to do this.
2) You could boot to a SD card or SAN if you have one as alternatives to a local boot disk thus giving you all 5 disk slots. HP sells I believe 8GB and 32GB SDCards for this purpose and they are much cheaper than a hard disk. This is what most of my customers are doing anyway even without Virtual SAN.
