System requirements
Please make sure to meet the minimum system requirements described here: https://www.universal-messenger.de/knowledge-base/intern/doc-en/Installation/Voraussetzungen.html
Architectural considerations and preparation
Before installation it is necessary to make considerations about the system architecture and to collect the credentials needed. All options can be changed afterwards.
The following questions must be answered:
Which license will you use?
Obtain a license file
Will you use the embedded Apache Tomcat or will you use a manually installed one or the one provided by your Linux distribution?
Which SQL database will you use?
Collect connection information and credentials
How should the Universal Messenger send e-mails? Note that the UM itself is not an MTA but rather an MTU. It will always need an SMTP server or an external e-mail sending service. There are many considerations about which is the best way to send e-mails in a way that it will not harm the MTA’s reputation, especially if you are planning to send a lot of e-mails.
Collect connection information and credentials before installation.
Which e-mail address(es) will be used to send the e-mails, i.e. what will be the sender address in the e-mail?
Collect e-mail addresses and sender names.
If and how will you cope with bounces or auto-replies? Will you use a technical sender e-mail address (envelope sender) which will be able to receive bounces and auto-replies? If so, can the Universal Messenger connect to an IMAP mailbox to read those e-mails?
Collect technical sender e-mail address
Collect IMAP connection information and credentials
Will the MTA for the technical sender e-mail address be able to use Variable envelope return path, i.e. an e-mail address which consists of a fixed part and a variable part.
A deep dive into the MTA topic can be found here: Sending e-mails