It actually works on a pi 2 (1Go RAM) but it is very slow
so if you are alone on the server “1 GB,1 Intel CPU,25 GB NVMe SSDs” might work but I would put 2 Go as minimal for the ram
the raspberry is a Linux script to install all DHIS2 components, I actually use my DEV server script to create the raspberry one(I remove some parts, added the wifi …) you can see in it the RAM config of TOMCAT/POSTGRES depending of the RAM of your server (Xsmall :1g, small:2g, medium:4g large: 8g )