My current project involves sending computers to clients that they will plug into their network. These computers fill the role of a web server, primarily. During a peak hour one of these servers will serve 10-20GB of mostly static content, and that content is updated locally or remotely with some frequency. Using consumer grade small form factor devices for this project is proving to be a bad idea due to failure rates and inconsistent hardware availability, and occasionally due to I/O and memory bottlenecks.
What are some widespread standard options, in terms of form factor and manufacturers, for this sort of project?
The OS for this device is CentOS 6, possibly 7 at some point in the future. Our current solution is approx 2"x8"x8". Slightly larger would be acceptable, but not as large as an ITX PC. We are handling backup and software security ourselves, and do not need hardware security features.