7.2. Upgrading a RHEV Hypervisor with local media

To upgrade an existing hypervisor from a local CD-ROM or USB device, insert the installation media and ensure the system boots from it. Boot the kernel with the upgrade parameter. This will automatically upgrade and reboot the system, rather than taking you to the interactive configuration menu. For more information, refer to Section 5.2.6, “Other parameters”.
ISOLINUX 3.11 2005-09-02  Copyright (C) 1994-2005 H. Peter Anvin
This is the Red Hat Enterprise Virtualization Hypervisor 5.7-2.2 (4.2)
- to boot press the <ENTER> key
or type linux and press the <ENTER> key.
- Extra kernel command line parameters can be passed following the 
linux keyword.
- Boot parameters summary:
BOOTIF=link|eth*|<MAC>(pxelinux format)
storage_init=[usb|scsi|cciss[:serial#]]|/dev/...
storage_vol=:SWAP_MB::CONFIG_MB:LOGGING_MB:DATA_MB
mem_overcommit=<overcommit_ratio>
upgrade
ip=<client-ip> netmask=<netmask> gateway=<gw-ip>
vlan=<VLAN-id>
dns=server[:server]
ntp=server[:server]
hostname=fqdn
management_server=RHEVM-host[:port]
netconsole_server=RHEVM-host[:port]
boot: linux upgrade

Figure 7.4. Booting with the upgrade parameter