openstack/openstack-manuals
Code Issues Proposed changes

Adds script for Admin User Guide migrating a VM to another host

Browse Source 
Change-Id: I83122fb3e0a1ea1083fe8df0baa7a55f1b432fea
This commit is contained in:
Anne Gentle 2014-05-22 19:33:12 -05:00 committed by Matthew Kassawara
parent e973d520c4
commit 0ae6e59898
4 changed files with 108 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
doc/user-guide-admin/roadmap.rst
View File

@ -18,5 +18,6 @@ including great descriptions of fields and why you set a setting
Wishlist tasks:
- Get examples of common tasks from real admins and add to this guide as how-to: migration of VM from one host to another, quota management, targeting launch on a particular compute node
- Create flavor example - also refer to from Ops Guide (Anne Gentle todo)
- Migrations examples (Anne Gentle todo)
- Create tenant example with CLI
- Replace all individual client commands (like keystone, nova) with openstack client commands

3
doc/user-guide-admin/section_cli_admin_manage_environment.xml
View File

@ -6,8 +6,9 @@
<xi:include href="section_cli_nova_specify_host.xml"/>
<?hard-pagebreak?>
<xi:include href="../common/section_cli_nova_evacuate.xml"/>
<xi:include href="section_cli_nova_migrate.xml"/>
<?hard-pagebreak?>
<xi:include href="section_cli_nova_floating_ips.xml"/>
<?hard-pagebreak?>
<xi:include href="section_cli_admin_manage_stacks.xml"/>
</section>
</section>

31
doc/user-guide-admin/section_cli_nova_host_servers_migrate.xml Normal file
View File

@ -0,0 +1,31 @@
<?xml version="1.0" encoding="UTF-8"?>
<section xmlns="http://docbook.org/ns/docbook"
xmlns:xi="http://www.w3.org/2001/XInclude"
xmlns:xlink="http://www.w3.org/1999/xlink" version="5.0"
xml:id="nova_cli_host_servers_migrate">
<title>Migrate all instances to another compute host</title>
<para>When you want to move all instances from one compute host to
another, you can use the <command>nova
host-servers-migrate</command> command. The difference
between this command and the <command>nova evacuate</command>
command is that you can specify the host when evacuating. Also
when evacuating, you must configure shared storage on the
target host so that user data is preserved on the server disk.
See <link xlink:href="http://docs.openstack.org/user-guide/content/nova_cli_evacuate.html">Evacuate instances</link>.</para>
<procedure xml:id="migrate_host">
<step>
<para>To list the host you want to migrate, run:</para>
<screen><prompt>$</prompt> <userinput>nova service-list</userinput></screen>
</step>
<step>
<para>After selecting a host from the list, run this
command:
<screen><prompt>$</prompt> <userinput>nova host-servers-migrate <replaceable>HOST_NAME</replaceable></userinput></screen></para>
<para>Where <replaceable>HOST_NAME</replaceable> is the
name of the host you want the servers to go to.</para>
<para>All instances are booted from a new host while preserving
their current configurations, including ID, name, UUID, IP
address, and so on.</para>
</step>
</procedure>
</section>

74
doc/user-guide-admin/section_cli_nova_migrate.xml Normal file
View File

@ -0,0 +1,74 @@
<?xml version="1.0" encoding="UTF-8"?>
<section xmlns="http://docbook.org/ns/docbook"
xmlns:xi="http://www.w3.org/2001/XInclude"
xmlns:xlink="http://www.w3.org/1999/xlink" version="5.0"
xml:id="nova_cli_migrate_single">
<title>Migrate single instance to another compute host</title>
<para>When you want to move an instance from one compute host to another,
you can use the <command>nova migrate</command> command. The scheduler
chooses the destination compute host based on its settings. This process
does not assume that the instance has shared storage available on the
target host.</para>
<procedure xml:id="migrate_single">
<step>
<para>To list the VMs you want to migrate, run:</para>
<screen><prompt>$</prompt> <userinput>nova list</userinput></screen>
</step>
<step>
<para>After selecting a VM from the list, run this command where
<replaceable>VM_ID</replaceable> is set to the ID in the list
returned in the previous step:</para>
<screen><prompt>$</prompt> <userinput>nova show <replaceable>VM_ID</replaceable></userinput></screen>
</step>
<step>
<para>Now, use the <command>nova migrate</command> command:</para>
<screen><prompt>$</prompt> <userinput>nova migrate <replaceable>VM_ID</replaceable></userinput></screen>
</step>
<step performance="optional">
<para>To migrate of an instance and watch the status, use this
example script:</para>
<programlisting language="bash">#!/bin/bash
# Provide usage
usage() {
echo "Usage: $0 VM_ID"
exit 1
}
[[ $# -eq 0 ]] &amp;&amp; usage
# Migrate the VM to an alternate hypervisor
echo -n "Migrating instance to alternate host"
$VM_ID=$1
nova migrate $VM_ID
VM_OUTPUT=`nova show $VM_ID`
VM_STATUS=`echo "$VM_OUTPUT" | grep status | awk '{print $4}'`
while [[ "$VM_STATUS" != "VERIFY_RESIZE" ]]; do
echo -n "."
sleep 2
VM_OUTPUT=`nova show $VM_ID`
VM_STATUS=`echo "$VM_OUTPUT" | grep status | awk '{print $4}'`
done
nova resize-confirm $VM_ID
echo " instance migrated and resized."
echo;
# Show the details for the VM
echo "Updated instance details:"
nova show $VM_ID
# Pause to allow users to examine VM details
read -p "Pausing, press &lt;enter&gt; to exit."</programlisting>
<note>
<para>If you see this error, it means you are either trying the
command with the wrong credentials, such as a non-admin
user, or the <filename>policy.json</filename> file prevents
migration for your user.
<screen><computeroutput>ERROR (Forbidden): Policy doesn't allow compute_extension:admin_actions:migrate to be performed. (HTTP 403)</computeroutput></screen></para>
</note>
<para>The instance is booted from a new host, but preserves its
configuration including its ID, name, any metadata, IP address,
and other properties.</para>
</step>
</procedure>
</section>