The estimate of 19KW gives a rough estimated requirement of ~90A @ 208v. 4 x 208v 30A circuits gives a total of 120A -- of which they can only be used at 80% c

The estimate of 19KW gives a rough estimated requirement of ~90A @ 208v. 4 x 208v 30A circuits gives a total of 120A -- of which they can only be used at 80% capacity, so that gives you 96A usable -- without redundancy. My initial feelings (eyeballing it) are you should be looking for 3 full racks, 2x208V@30A in each. As a juniper shop, we implemented the 2xQFX 5100 48T (in virtual chassis) + ex4300 for remote access per rack. This will be a decision based on your local expertise though. I also looked hard into the twin boxes -- but power to the rack in the end ruled the day, and it made not much of a difference to use the 1U boxes. Don't forget about out of band (serial for the switching gear). We've been using OpenGear.com for this stuff with 4G-LTE builtin. VPN access to access console devices? Any site-to-site VPN needs? Also, I would consider not pre-purchasing N times your required horsepower/disk if you can avoid it, but rather add in pre-planned yearly, or biannually stages. As the CEO of a cloud hosting & server management company -- I have much more to say about this if you would like to chat via phone or email anytime.