Go to: https://yourserverip:2087
Enter your root username and password.

From the left-hand sidebar, navigate to:
Home → System Reboot

Graceful Server Reboot
Forceful Server Reboot
Graceful Server Reboot
Safely stops all services before rebooting.
Prevents data corruption.
Recommended in most cases.
Forceful Server Reboot
Immediately reboots the server without waiting for services to stop.
Use only if the server is unresponsive.
Click Proceed or Yes when prompted.
The server will go offline briefly and restart.
Wait 1–2 minutes, then log back into WHM.