HP Integrity BL890c - i2 Server Software Manual page 37

3 Debugging HP Virtual Machines guests
HP Virtual Machines (HPVM) is a soft partitioning and virtualization technology that provides
operating system isolation with CPU allocation and shared I/O. HPVM enables a single Integrity
server to emulate multiple virtual machines running distinct operating systems and environments.
The Virtual Machines solution consists of two components:
• A VM host (the physical system on which the virtual machines reside)
• One or more virtual machines, also known as guests
Virtual machines, or guests, are abstractions of real, physical machines. They are fully-loaded,
operational systems, complete with operating system, system management utilities, applications,
and networks, all running in the virtual machine environment that you set up for them. You
boot and manage guests using the same storage media and procedures that you would if the
guest operating system were running on its own dedicated physical hardware platform.
HPVM Windows guest debug process
HPVM Version 2.0 supports Windows kernel debugging through the host serial ports. Usually
only one such port is available on low-end systems. Therefore, without an add-in serial port
card, you can debug only one Windows guest at a time. To debug multiple guests on low-end
systems (or even a single guest on mid-range or high-end systems, such as rx7640, rx8640, and
Superdome), you need a serial port card.
To enable kernel debugging for an HPVM Windows guest, complete the following steps:
1. Locate the target guest's configuration file: vmm_config.current (the host maintains all
per-guest information in the /var/opt/hpvm/guests/$guest_name$ directory).
2. Open the vmm_config.current file and add the following lines to it:
# Debugging uart definition
uart(7,1)=/dev/ttyXX
where XX is the tty belonging to the available host serial port.
NOTE:
over a LAN, you would add the following line to the guest configuration file instead:
tunable = 0xNNNNNNNN wdbg
where NN NN NN NN is the static IP address (in hex) of the desired debug port.
3. Reboot the guest to apply the change (unless it is already off).
Each guest can have only one such entry, but each guest on a given host can attach to a unique
tty port to enable multiguest debugging. The procedure for physically connecting to the host
machine is identical to the local debugging connection methods used on other Integrity servers
(see Chapter 1). The debugger simply attaches to a given serial port on the host using a
null-modem cable.
Also, you must modify the Windows guest boot entry in the virtual EFI shell the same way that
you do when debugging entire Integrity servers, as described in previous chapters. The only
restriction is that you must use a baud rate of 38400bps. You must specify this in the NVRAM
boot entry for the operating system and in the kernel debugger configuration of the debugger
machine.
The instructions above are for debugging locally over the serial port. To debug
HPVM Windows guest debug process 37