For 50 students all online concurrently, I'd say 1vcpu and 4GB memory is a safe bet. Probably more if you are using Edrys for remote labs, which use more resour

For 50 students all online concurrently, I'd say 1vcpu and 4GB memory is a safe bet. Probably more if you are using Edrys for remote labs, which use more resources and send more information at a higher rate. We've tested this architecture with ~200 students, which worked fine with a server hosted on an old Thinkpad laptop (4GB of memory IIRC). To scale Edrys horizontally, you just host multiple separate instances that are used for different classes, since there is no shared database and all auth/auth is stateless.