Create file.
touch /etc/systemd/system/delayed-script.service
Fill it.
[Unit]
Description=Run Script as Cognos User 5 Minutes After Boot
After=network.target
[Service]
Type=simple
User=user
Group=group
ExecStartPre=/bin/sleep 300
ExecStart=/opt/somescript.sh
Restart=no
RemainAfterExit=yes
[Install]
WantedBy=multi-user.target
enable it and reboot server
systemctl enable delayed-script.service
shutdown -r now
This will start script in 5 min after server reboot as “user” user