создайте файл /etc/systemd/system/icecast.service и запишите в него
[Unit]
Description=Icecast Network Audio Streaming Server
After=network.target
[Service]
ExecStart=/opt/icecast/latest/bin/icecast -c /opt/icecast/latest/etc/icecast.xml -b
ExecReload=/bin/kill -HUP $MAINPID
[Install]
WantedBy=multi-user.target
автозапуск: systemctl enable icecast.service
start: systemctl start icecast.service
stop: systemctl stop icecast.service
reload: systemctl reload icecast.service
про добавление в ispmanager, к сожалению, не скажу
