Add solution for when instance log output is empty

A Linux instance has to be configured to send log output to the serial
console whenever the Compute service collects log output from there.
Otherwise, the log output will be empty. Added this as a
troubleshooting tip to Cloud Admin Guide.

Change-Id: I5adb28c2d73c41792c1d67f51e11edfc7474ed99
Closes-Bug: #1284962
This commit is contained in:
Don Domingo 2014-02-26 14:25:06 +10:00
parent 1c6a4f2daf
commit 53b7635a19

View File

@ -13,7 +13,7 @@
compute node. This section shows you how to troubleshoot
Compute.</para>
<section xml:id="log-files-for-openstack-compute">
<title>Compute log files</title>
<title>Compute service logging</title>
<para>Compute stores a log file for each service in
<filename>/var/log/nova</filename>. For example,
<filename>nova-compute.log</filename> is the log for
@ -147,7 +147,26 @@
returns an error:</para>
<screen><prompt>#</prompt> <userinput>virsh create libvirt.xml</userinput></screen>
</section>
</section>
<section xml:id="section_compute-empty-log-output">
<title>Empty log output for Linux instances</title>
<para>You can view the log output of running instances
from either the <guilabel>Log</guilabel> tab of the
dashboard or the output of
<command>nova console-log</command>. In some cases, the
log output of a running Linux instance will be empty or
only display a single character (for example,
the <keycap>?</keycap> character).</para>
<para>This occurs when the Compute service attempts to
retrieve the log output of the instance via a serial
console while the instance itself is not configured to
send output to the console. To rectify this, append the
following parameters to kernel arguments specified in the
instance's boot loader:</para>
<screen>console=tty0 console=ttyS0,115200n8</screen>
<para>Upon rebooting, the instance will be configured to
send output to the Compute service.</para>
</section>
</section>
<section xml:id="reset-state">
<title>Reset the state of an instance</title>
<para>If an instance remains in an intermediate state, such as