xen Ctr + Alt + Del

If you hit CTRL+ALT+Delete your host will go down under CentOS Linux 5.x. The solution is hit CTRL key thrice. Now it will disable CTRL+ALT+Del for host. Next just hit alt+del to complete guest CTRL+ALT+Del cycle. Alternatively, you can type the following on host to shutdown vps: xm shutdown myGuestVpsOsName