Log xml in libvirt _create_domain failures

When an error occurs defining, launching or enabling hairpin mode on a
libvirt domain, log the xml for reproduction and analysis.

Fixes bug 1183534

Change-Id: Ic8f1d11c5a92779c686b7248895bbc6f2cfdbf0b

1 files changed, 21 insertions, 3 deletions

diff --git a/nova/virt/libvirt/driver.py b/nova/virt/libvirt/driver.py
index 6cfa2c7c7..90695d1c3 100755
--- a/nova/virt/libvirt/driver.py
+++ b/nova/virt/libvirt/driver.py
@@ -2481,10 +2481,28 @@ class LibvirtDriver(driver.ComputeDriver):
                                  use_cow=CONF.use_cow_images)
 
         if xml:
-            domain = self._conn.defineXML(xml)
+            try:
+                domain = self._conn.defineXML(xml)
+            except Exception as e:
+                LOG.error(_("An error occurred while trying to define a domain"
+                            " with xml: %s") % xml)
+                raise e
+
         if power_on:
-            domain.createWithFlags(launch_flags)
-        self._enable_hairpin(domain.XMLDesc(0))
+            try:
+                domain.createWithFlags(launch_flags)
+            except Exception as e:
+                with excutils.save_and_reraise_exception():
+                    LOG.error(_("An error occurred while trying to launch a "
+                                "defined domain with xml: %s") %
+                              domain.XMLDesc(0))
+
+        try:
+            self._enable_hairpin(domain.XMLDesc(0))
+        except Exception:
+            with excutils.save_and_reraise_exception():
+                LOG.error(_("An error occurred while enabling hairpin mode on "
+                            "domain with xml: %s") % domain.XMLDesc(0))
 
         # NOTE(uni): Now the container is running with its own private mount
         # namespace and so there is no need to keep the container rootfs