Para-Virtualized Guest Console Access; Fully Virtualized Guest Console Access; Common Xen Problems - Red Hat ENTERPRISE LINUX 5 - VIRTUALIZATION GUIDE Manual

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:
Itanium serial console troubleshooting
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, refer to
Chapter 28, Configuring
ttywatch ---name myhost ---port -/dev/ttyS0
This pipes the output from /dev/ttyS0 into the file /var/log/ttywatch/myhost.log .

33.7. Para-virtualized 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.

33.8. Fully virtualized 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 Full 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 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.

33.9. Common Xen problems

When attempting to start the xend service, nothing happens. Type virsh list and receive the
following:
Error: Error connecting to xend: Connection refused. Is xend running?
Try to run xend start manually and receive more errors:
Error: Could not obtain handle on privileged command interfaces (2 = No such file or
directory)
ELILO.
Para-virtualized guest console access
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