Tips and tricks: How do I configure Xendump on Red Hat Enterprise Linux 5?

Contributed by Eugene Teo

Release Found: Red Hat Enterprise Linux 5

Xendump is a facility for capturing vmcore dumps from Xen guests. It is built-in to the Xen Hypervisor. Vmcore dumps are useful for analysing system crashes, using the tool crash. Crash is similar to traditional Unix crash tool, and it provides stack traces and other debugging functionality for locating problem areas causing the crashes. A similar facility, but meant for non Xen-enabled kernels, is called Kdump. To find out more about how Kdump works, please read kbase.redhat.com/faq/FAQ_105_9036.shtm.

To configure Xendump follow the steps described below:

1. Enable the Xendump facility. Edit /etc/xen/xend-config.sxp and change the following line

   #(enable-dump no)
   

   to:

   (enable-dump yes)
   

2. Restart the xen daemon:

   # service xend restart
   

3. To make sure that Xendump works, start a Xen guest:

   # xm create /etc/xen/<domain>
   

4. Capture a vmcore by typing:

   # xm dump-core <domain-name> <vmcore-file>

Take note that, right now, Xendump can be configured to capture vmcore dumps of para-virtualized (PV) Xen guests automatically upon a crash. However, vmcore dumps from fully-virtualized (FV) Xen guests can only be taken manually by running the xm dump-core command.

This entry was posted by the editorial team on Monday, October 15th, 2007 at 8:48 am and is filed under tips and tricks, technical. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.