This book is designed as an Ubuntu 18.04 LTS Server administration and reference source, covering the Ubuntu servers and their support applications. Server tools are covered as well as the underlying configuration files and system implementations. The emphasis is on what administrators will need to know to perform key server support and management tasks. Coverage of the systemd service management system is integrated into the book. Topics covered include software management, systemd service management, systemd-networkd and Netplan network configuration, AppArmor security, OpenSSH, the Chrony time server, and Ubuntu cloud services. Key servers are examined, including Web, FTP, CUPS printing, NFS, and Samba Windows shares. Network support servers and applications covered include the Squid proxy server, the Domain Name System (BIND) server, DHCP, distributed network file systems, IPtables firewalls, and cloud computing.