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Troubleshooting
If you experience odd behavior, application crashes, or have other issues with a XenServer host, this chapter
is meant to help you solve the problem if possible and, failing that, describes where the application logs
are located and other information that can help your Citrix Solution Provider and Citrix track and resolve
the issue.
Troubleshooting of installation issues is covered in the XenServer Installation Guide. Troubleshooting of
Virtual Machine issues is covered in the XenServer Virtual Machine Installation Guide.
Important:
We recommend that you follow the troubleshooting information in this chapter solely under the guidance
of your Citrix Solution Provider or Citrix Support.
Citrix provides two forms of support: you can receive free self-help support on the Support site, or you may
purchase our Support Services and directly submit requests by filing an online Support Case. Our free web-
based resources include product documentation, a Knowledge Base, and discussion forums.
XenServer host logs
XenCenter can be used to gather XenServer host information. Click on Get Server Status Report... in
the Tools menu to open the Server Status Report wizard. You can select from a list of different types of
information (various logs, crash dumps, etc.). The information is compiled and downloaded to the machine
that XenCenter is running on. For details, see the XenCenter Help.
Additionally, the XenServer host has several CLI commands to make it simple to collate the output of logs
and various other bits of system information using the utility xen-bugtool. Use the xe command host-
bugreport-upload to collect the appropriate log files and system information and upload them to the Citrix
Support ftp site. Please refer to the section called “host-bugreport-upload” for a full description of this
command and its optional parameters. If you are requested to send a crashdump to Citrix Support, use the
xe command host-crashdump-upload. Please refer to the section called “host-crashdump-upload” for a
full description of this command and its optional parameters.
It is possible that sensitive information might be written into the XenServer host logs.
By default, the server logs report only errors and warnings. If you need to see more detailed information,
you can enable more verbose logging. To do so, use the host-loglevel-set command:
host-loglevel-set log-level=level
where level can be 0, 1, 2, 3, or 4, where 0 is the most verbose and 4 is the least verbose.
Log files greater than 5 MB are rotated, keeping 4 revisions. The logrotate command is run hourly.
Sending host log messages to a central server
Rather than have logs written to the control domain filesystem, you can configure a XenServer host to write
them to a remote server. The remote server must have the syslogd daemon running on it to receive the logs
and aggregate them correctly. The syslogd daemon is a standard part of all flavors of Linux and Unix, and
third-party versions are available for Windows and other operating systems.
To write logs to a remote server
1. Set the syslog_destination parameter to the hostname or IP address of the remote server where you
want the logs to be written:
