I’ve not seen in any guide mentioned it anywhere in any guide so I post it here.
In Oracle Cloud Service there is Ubuntu’s firewall that blocking ports, without which you can’t connect to the teamspeak server, so to resolve this issue you need to add ports exceptions by following command
apt install -y firewalld && firewall-cmd --state && firewall-cmd --add-port=9987/udp && firewall-cmd --add-port=10011/tcp && firewall-cmd --add-port=10022/tcp && firewall-cmd --add-port=10080/tcp && firewall-cmd --add-port=30033/tcp && firewall-cmd --add-port=41144/tcp && firewall-cmd --add-port=9987/udp --permanent && firewall-cmd --add-port=10011/tcp --permanent && firewall-cmd --add-port=10022/tcp --permanent && firewall-cmd --add-port=10080/tcp --permanent && firewall-cmd --add-port=30033/tcp --permanent && firewall-cmd --add-port=41144/tcp --permanent
and just incase there is one-line command to run the latest ts3 server, maybe someone need it
sudo su
apt-get -y update && apt-get -y upgrade && adduser -q --gecos GECOS --disabled-login teamspeak && wget $(curl -s TeamSpeak Downloads | TeamSpeak | grep -o ‘https://files.teamspeak-services.com/releases/server/.*/teamspeak3-server_linux_amd64-.*.tar.bz2’ | head -n1) && tar xvf teamspeak3-server_linux_amd64* && cd teamspeak3-server_linux_amd64 && mv * /home/teamspeak && cd … && rm -rf teamspeak3-server* && touch /home/teamspeak/.ts3server_license_accepted && chown -R teamspeak:teamspeak /home/teamspeak && echo -e “[Unit]\nDescription=TeamSpeak 3 Server\nAfter=network.target\n\n[Service]\nWorkingDirectory=/home/teamspeak/\nUser=teamspeak\nGroup=teamspeak\nType=forking\nExecStart=/home/teamspeak/ts3server_startscript.sh start inifile=ts3server.ini\nExecStop=/home/teamspeak/ts3server_startscript.sh stop\nPIDFile=/home/teamspeak/ts3server.pid\nRestartSec=15\nRestart=always\n\n[Install]\nWantedBy=multi-user.target” >> /lib/systemd/system/teamspeak.service && systemctl --system daemon-reload && systemctl enable teamspeak.service && systemctl start teamspeak.service && systemctl status teamspeak.service && grep -hoE “token=(.+)” /home/teamspeak/logs/*
