This chapter deals with issues you may encounter with the Red Hat Enterprise Linux hosts and fully virtualized guests using the para-virtualized drivers
29.1. Red Hat Enterprise Linux 5 Virtualization log file and directories
Red Hat Enterprise Linux 5 Virtualization related log file
In Red Hat Enterprise Linux 5, the log file written by the xend daemon and the qemu-dm process are all kept in the following directories:
/var/log/xen/
directory holding all log file generated by the xend daemon and qemu-dm process.
xend.log
This logfile is used by xend to log any events generate by either normal system events or operator initiated events.
virtual machine operations such as create, shutdown, destroy etc are all logged in this logfile.
Usually this logfile will be the first place to look at in the event of a problem. In many cases you will be able to identify the root cause by scanning the logfile and review the entries logged just prior to the actual error message.
xend-debug.log
used to record error events from xend and its subsystems (such as framebuffer and Python scripts etc..)
xen-hotplug.log
used to log events from hotplug events.
events such as devices not coming online or network bridges not online will be logged in this file
qemu-dm.PID.log
this file is create by the qemu-dm process which is started for each fully-virtualized guest.
the PID will be replaced with the PID of the process of the related qemu-dm process
You can retrieve the PID for a given qemu-dm process using the ps command and in looking at the process arguments you can identify the virtual machine the qemu-dm process belongs to.
If you are troubleshooting a problem with the virt-manager application you can also review the logfile generated by it. The logfile for virt-manager will be in a directory called .virt-manager in the user's home directory whom ran virt-manager. This directory will usually be ~/.virt-manager/virt-manager.
Note
The logfile is overwritten every time you start virt-manager. If you are troubleshooting a problem with virt-manager make sure you save the logfile before you restart virt-manager after an error has occurred.
Red Hat Enterprise Linux 5 Virtualization related directories
There are a few other directories and files which may be of interest when troubleshooting a Red Hat Enterprise Linux 5 Virtualization environment:
/var/lib/xen/images/
the standard directory for file based virtual machine images.
/var/lib/xen/xend-db/
directory that hold the xend database which is generated every time the daemon is restarted.
/etc/xen/
holds a number of configuration files used to tailor your Red Hat Enterprise Linux 5 Virtualization environment to suite your local needs
xend-config.sxp is the main configuration for the xend daemon. It used to enable/disable specific functionality of the Xen daemon, and to configure the callouts to Xen networking.
/var/xen/dump/
hold dumps generate by virtual machines or when using the xm dump-core command.
/proc/xen/
has a number of entries which can be used to retrieve additional information:
