Installation guide

module /vmlinuz-2.618-8.el5xen ro root=LABEL=/rhgb quiet console=xvc console=tty
xencons=xvc
module /initrd-2.6.18-8.el5xen.img
The sync_console can help determine a problem that causes hangs with asynchronous hypervisor
console output, and the "pnpacpi=off" works around a problem that breaks input on the serial
console. The parameters "console=ttyS0" and "console=tty" means that kernel errors get
logged with on both the normal VGA console and on the serial console. Then you can install and set
up ttywatch to capture the data on a remote host connected by a standard null-modem cable.
For example, on the remote host you could type:
Note
To access the hypervisor via a serial console on the Itanium® architecture you must enable
the console in ELILO. For more information on configuring ELILO, see Chapter 30, Configuring
ELILO.
ttywatch --name myhost --port /dev/ttyS0
This pipes the output from /dev/ttyS0 into the file /var/log/ttywatch/myhost.log .
35.7. Para-virt ualized guest console access
Para-virtualized guest operating systems automatically has a virtual text console configured to
transmit data to the host operating system. Connect to a guest's virtual console with the following
command:
# virsh console [guest name, ID or UUID]
You can also use virt-manager to display the virtual text console. In the guest console window,
select Serial Console from the View menu.
35.8. Fully virt ualized guest console access
Fully virtualized guest operating systems automatically has a text console configured for use, but the
difference is the kernel guest is not configured. To enable the guest virtual serial console to work with
the fully virtualized guest, you must modify the guest's grub.conf file, and include the 'console
=ttyS0 console=tty0' parameter. This ensures that the kernel messages are sent to the virtual
serial console (and the normal graphical console). To use the guest's serial console, you must edit
the libvirt configuration file. On the host, access the serial console with the following command:
# virsh console
You can also use virt-manager to display the virtual text console. In the guest console window,
select Serial Console from the View menu.
35.9. Common Xen problems
When attempting to start the xend service, nothing happens. Type virsh list and receive the
following:
⁠Chapt er 35. T roub leshoo t ing Xen
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