Make sure the server has Intel SGX capability and is enabled in the Bios. Min hardware is 8Core, 32GB and should not be virtualized. AWS, Twillio, Google, Apple, Android activated accounts with root access are required. The aqnouch guide is obsolete, and is just for Server 2.88, current version is 3.21. Configuration and deployment is not the job of a Java Developer, but that of an Infrastructure Architect. The code "Signal-Server" is just for auditing purposes and not expected to be used on production servers. There are a lot of missing components in the current code deployed compared to the WhisperSystems hosted server which powers the signal app which is getting popular.