Notes for installing Oracle 18c XE on OraLinux 7(.6)

1) RAM must be >= 1 GB. Better if 2GB+. There are some tricks about installing with less RAM: https://community.oracle.com/thread/4185400

2) When run configure the next error was appears: [FATAL] [DBT-06103] The port (5,500) is already in use. INFO: Read: ACTION: Specify a free port

Solution: add server to /etc/hosts (#ipadrress hostname short_hostname)

3) Open 5500 port in firewall and install Adobe Flash Player for using Enterprise Manager