698 lines
35 KiB
XML
698 lines
35 KiB
XML
<section xml:id="ibm-storwize-svc-driver"
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xmlns="http://docbook.org/ns/docbook"
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xmlns:xi="http://www.w3.org/2001/XInclude"
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xmlns:xlink="http://www.w3.org/1999/xlink" version="5.0">
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<title>IBM Storwize family and SVC volume driver</title>
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<para>The volume management driver for Storwize family and SAN
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Volume Controller (SVC) provides OpenStack Compute instances
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with access to IBM Storwize family or SVC storage
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systems.</para>
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<section xml:id="ibm-storwize-svc-driver1">
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<title>Configure the Storwize family and SVC system</title>
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<simplesect>
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<title>Network configuration</title>
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<para>The Storwize family or SVC system must be configured
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for iSCSI, Fibre Channel, or both.</para>
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<para>If using iSCSI, each Storwize family or SVC node
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should have at least one iSCSI IP address. The IBM
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Storwize/SVC driver uses an iSCSI IP address
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associated with the volume's preferred node (if
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available) to attach the volume to the instance,
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otherwise it uses the first available iSCSI IP address
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of the system. The driver obtains the iSCSI IP address
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directly from the storage system; you do not need to
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provide these iSCSI IP addresses directly to the
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driver.</para>
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<note>
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<para>If using iSCSI, ensure that the compute nodes
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have iSCSI network access to the Storwize family
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or SVC system.</para>
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</note>
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<note>
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<para>OpenStack Nova's Grizzly version supports iSCSI
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multipath. Once this is configured on the Nova
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host (outside the scope of this documentation),
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multipath is enabled.</para>
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</note>
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<para>If using Fibre Channel (FC), each Storwize family or
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SVC node should have at least one WWPN port
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configured. If the
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<literal>storwize_svc_multipath_enabled</literal>
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flag is set to True in the Cinder configuration file,
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the driver uses all available WWPNs to attach the
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volume to the instance (details about the
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configuration flags appear in the <link
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linkend="ibm-storwize-svc-driver2"> next
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section</link>). If the flag is not set, the
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driver uses the WWPN associated with the volume's
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preferred node (if available), otherwise it uses the
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first available WWPN of the system. The driver obtains
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the WWPNs directly from the storage system; you do not
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need to provide these WWPNs directly to the
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driver.</para>
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<note>
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<para>If using FC, ensure that the compute nodes have
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FC connectivity to the Storwize family or SVC
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system.</para>
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</note>
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</simplesect>
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<simplesect>
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<title>iSCSI CHAP authentication</title>
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<para>If using iSCSI for data access and the
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<literal>storwize_svc_iscsi_chap_enabled</literal>
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is set to <literal>True</literal>, the driver will
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associate randomly-generated CHAP secrets with all
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hosts on the Storwize family system. OpenStack compute
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nodes use these secrets when creating iSCSI
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connections. <note>
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<para>CHAP secrets are added to existing hosts as
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well as newly-created ones. If the CHAP option
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is enabled, hosts will not be able to access
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the storage without the generated
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secrets.</para>
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</note>
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<note>
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<para>Not all OpenStack Compute drivers support
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CHAP authentication. Please check
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compatibility before using.</para>
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</note>
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<note>
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<para>CHAP secrets are passed from OpenStack Block
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Storage to Compute in clear text. This
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communication should be secured to ensure that
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CHAP secrets are not discovered.</para>
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</note></para>
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</simplesect>
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<simplesect>
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<title>Configure storage pools</title>
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<para>Each instance of the IBM Storwize/SVC driver
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allocates all volumes in a single pool. The pool
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should be created in advance and be provided to the
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driver using the
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<literal>storwize_svc_volpool_name</literal>
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configuration flag. Details about the configuration
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flags and how to provide the flags to the driver
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appear in the <link linkend="ibm-storwize-svc-driver2"
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> next section</link>.</para>
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</simplesect>
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<simplesect>
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<title>Configure user authentication for the
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driver</title>
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<para>The driver requires access to the Storwize family or
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SVC system management interface. The driver
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communicates with the management using SSH. The driver
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should be provided with the Storwize family or SVC
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management IP using the <literal>san_ip</literal>
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flag, and the management port should be provided by
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the <literal>san_ssh_port</literal> flag. By default,
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the port value is configured to be port 22
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(SSH).</para>
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<note>
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<para>
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Make sure the compute node running the <systemitem
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class="service">cinder-volume</systemitem>
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management driver has SSH network access to the
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storage system.
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</para>
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</note>
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<para>To allow the driver to communicate with the Storwize
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family or SVC system, you must provide the driver with
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a user on the storage system. The driver has two
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authentication methods: password-based authentication
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and SSH key pair authentication. The user should have
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an Administrator role. It is suggested to create a new
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user for the management driver. Please consult with
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your storage and security administrator regarding the
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preferred authentication method and how passwords or
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SSH keys should be stored in a secure manner.</para>
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<note>
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<para>When creating a new user on the Storwize or SVC
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system, make sure the user belongs to the
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Administrator group or to another group that has
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an Administrator role.</para>
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</note>
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<para>If using password authentication, assign a password
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to the user on the Storwize or SVC system. The driver
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configuration flags for the user and password are
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<literal>san_login</literal> and
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<literal>san_password</literal>,
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respectively.</para>
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<para>If you are using the SSH key pair authentication,
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create SSH private and public keys using the
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instructions below or by any other method. Associate
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the public key with the user by uploading the public
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key: select the "choose file" option in the Storwize
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family or SVC management GUI under "SSH public key".
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Alternatively, you may associate the SSH public key
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using the command line interface; details can be found
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in the Storwize and SVC documentation. The private key
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should be provided to the driver using the
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<literal>san_private_key</literal> configuration
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flag.</para>
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</simplesect>
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<simplesect>
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<title>Create a SSH key pair with OpenSSH</title>
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<para>You can create an SSH key pair using OpenSSH, by
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running:</para>
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<screen><prompt>$</prompt> <userinput>ssh-keygen -t rsa</userinput></screen>
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<para>The command prompts for a file to save the key pair.
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For example, if you select 'key' as the filename, two
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files are created: <literal>key</literal> and
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<literal>key.pub</literal>. The
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<literal>key</literal> file holds the private SSH
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key and <literal>key.pub</literal> holds the public
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SSH key.</para>
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<para>The command also prompts for a pass phrase, which
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should be empty.</para>
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<para>The private key file should be provided to the
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driver using the <literal>san_private_key</literal>
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configuration flag. The public key should be uploaded
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to the Storwize family or SVC system using the storage
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management GUI or command line interface.</para>
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<note>
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<para>Ensure that Cinder has read permissions on the
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private key file.</para>
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</note>
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</simplesect>
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</section>
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<section xml:id="ibm-storwize-svc-driver2">
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<title>Configure the Storwize family and SVC driver</title>
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<simplesect>
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<title>Enable the Storwize family and SVC driver</title>
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<para>Set the volume driver to the Storwize family and SVC
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driver by setting the <literal>volume_driver</literal>
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option in <filename>cinder.conf</filename> as
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follows:</para>
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<programlisting>volume_driver = cinder.volume.drivers.ibm.storwize_svc.StorwizeSVCDriver</programlisting>
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</simplesect>
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<simplesect>
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<title>Storwize family and SVC driver options in
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cinder.conf</title>
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<para>The following options specify default values for all
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volumes. Some can be over-ridden using volume types,
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which are described below.</para>
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<table rules="all">
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<caption>List of configuration flags for Storwize
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storage and SVC driver</caption>
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<col width="40%"/>
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<col width="10%"/>
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<col width="12%"/>
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<col width="38%"/>
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<thead>
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<tr>
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<th>Flag name</th>
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<th>Type</th>
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<th>Default</th>
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<th>Description</th>
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</tr>
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</thead>
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<tbody>
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<tr>
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<td><para><literal>san_ip</literal></para>
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</td>
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<td><para>Required</para></td>
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<td><para/></td>
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<td><para>Management IP or host name</para>
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</td>
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</tr>
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<tr>
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<td><para><literal>san_ssh_port</literal></para>
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</td>
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<td><para>Optional</para></td>
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<td><para>22</para></td>
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<td><para>Management port</para></td>
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</tr>
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<tr>
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<td><para><literal>san_login</literal></para>
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</td>
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<td><para>Required</para></td>
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<td><para/></td>
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<td><para>Management login username</para>
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</td>
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</tr>
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<tr>
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<td><para><literal>san_password</literal></para>
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</td>
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<td><para>Required <footnote
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xml:id="storwize-svc-fn1">
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<para>The authentication requires
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either a password
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(<literal>san_password</literal>)
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or SSH private key
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(<literal>san_private_key</literal>).
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One must be specified. If both are
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specified, the driver uses only the
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SSH private key.</para>
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</footnote></para></td>
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<td><para/></td>
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<td><para>Management login password</para>
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</td>
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</tr>
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<tr>
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<td><para><literal>san_private_key</literal></para>
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</td>
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<td><para>Required <footnoteref
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linkend="storwize-svc-fn1"
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/></para></td>
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<td><para/></td>
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<td><para>Management login SSH private
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key</para>
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</td>
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</tr>
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<tr>
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<td><para>
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<literal>storwize_svc_volpool_name</literal></para>
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</td>
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<td><para>Required</para></td>
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<td><para/></td>
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<td><para>Default pool name for
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volumes</para></td>
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</tr>
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<tr>
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<td><para>
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<literal>storwize_svc_vol_rsize</literal></para>
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</td>
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<td><para>Optional</para></td>
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<td><para>2</para></td>
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<td><para>Initial physical allocation
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(percentage) <footnote
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xml:id="storwize-svc-fn3">
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<para>The driver creates
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thin-provisioned volumes by
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default. The
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<literal>storwize_svc_vol_rsize</literal>
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flag defines the initial physical
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allocation percentage for
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thin-provisioned volumes, or if set
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to <literal>-1</literal>, the
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driver creates full allocated
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volumes. More details about the
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available options are available in
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the Storwize family and SVC
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documentation.</para>
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</footnote></para></td>
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</tr>
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<tr>
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<td><para>
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<literal>storwize_svc_vol_warning</literal></para>
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</td>
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<td><para>Optional</para></td>
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<td><para>0 (disabled)</para></td>
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<td><para>Space allocation warning threshold
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(percentage) <footnoteref
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linkend="storwize-svc-fn3"
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/></para></td>
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</tr>
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<tr>
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<td><para>
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<literal>storwize_svc_vol_autoexpand</literal></para>
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</td>
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<td><para>Optional</para></td>
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<td><para>True</para></td>
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<td><para>Enable or disable volume auto expand
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<footnote xml:id="storwize-svc-fn4">
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<para>Defines whether
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thin-provisioned volumes can be
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auto expanded by the storage
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system, a value of
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<literal>True</literal> means that
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auto expansion is enabled, a value
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of <literal>False</literal>
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disables auto expansion. Details
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about this option can be found in
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the <literal>–autoexpand</literal>
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flag of the Storwize family and SVC
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command line interface
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<literal>mkvdisk</literal>
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command.</para>
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</footnote></para></td>
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</tr>
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<tr>
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<td><para>
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<literal>storwize_svc_vol_grainsize</literal></para>
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</td>
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<td><para>Optional</para></td>
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<td><para>256</para></td>
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<td><para>Volume grain size <footnoteref
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linkend="storwize-svc-fn3"/> in
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KB</para></td>
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</tr>
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<tr>
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<td><para>
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<literal>storwize_svc_vol_compression
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</literal></para>
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</td>
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<td><para>Optional</para></td>
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<td><para>False</para></td>
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<td><para>Enable or disable Real-time
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Compression <footnote
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xml:id="storwize-svc-fn5">
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<para>Defines whether Real-time
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Compression is used for the volumes
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created with OpenStack. Details on
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Real-time Compression can be found
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in the Storwize family and SVC
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documentation. The Storwize or SVC
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system must have compression
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enabled for this feature to
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work.</para>
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</footnote></para>
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</td>
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</tr>
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<tr>
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<td><para>
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<literal>storwize_svc_vol_easytier</literal></para>
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</td>
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<td><para>Optional</para></td>
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<td><para>True</para></td>
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<td><para>Enable or disable Easy Tier
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<footnote xml:id="storwize-svc-fn6">
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<para>Defines whether Easy Tier is
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used for the volumes created with
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OpenStack. Details on EasyTier can
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be found in the Storwize family and
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SVC documentation. The Storwize or
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SVC system must have Easy Tier
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enabled for this feature to
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work.</para>
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</footnote></para></td>
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</tr>
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<tr>
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<td><para>
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<literal>storwize_svc_vol_iogrp</literal></para>
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</td>
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<td><para>Optional</para></td>
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<td><para>0</para></td>
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<td><para>The I/O group in which to allocate
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vdisks</para></td>
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</tr>
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<tr>
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<td><para>
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<literal>storwize_svc_flashcopy_timeout
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</literal></para>
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</td>
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<td><para>Optional</para></td>
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<td><para>120</para></td>
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<td><para>FlashCopy timeout threshold
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<footnote xml:id="storwize-svc-fn7">
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<para>The driver wait timeout
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threshold when creating an
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OpenStack snapshot. This is
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actually the maximum amount of time
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that the driver waits for the
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Storwize family or SVC system to
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prepare a new FlashCopy mapping.
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The driver accepts a maximum wait
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time of 600 seconds (10
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minutes).</para>
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</footnote> (seconds)</para></td>
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</tr>
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<tr>
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<td><para>
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<literal>storwize_svc_connection_protocol
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</literal></para>
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</td>
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<td><para>Optional</para></td>
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<td><para>iSCSI</para></td>
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<td><para>Connection protocol to use
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(currently supports 'iSCSI' or
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'FC')</para></td>
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</tr>
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<tr>
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<td><para>
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<literal>storwize_svc_iscsi_chap_enabled
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</literal></para>
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</td>
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<td><para>Optional</para></td>
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<td><para>True</para></td>
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<td><para>Configure CHAP authentication for
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iSCSI connections</para></td>
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</tr>
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<tr>
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<td><para>
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<literal>storwize_svc_multipath_enabled
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</literal></para>
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</td>
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<td><para>Optional</para></td>
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<td><para>False</para></td>
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<td><para>Enable multipath for FC connections
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<footnote xml:id="storwize-svc-fn8">
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<para>Multipath for iSCSI
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connections requires no
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storage-side configuration and is
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enabled if the compute host has
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multipath configured.</para>
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</footnote></para></td>
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</tr>
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<tr>
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<td><para>
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<literal>storwize_svc_multihost_enabled
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</literal></para>
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</td>
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<td><para>Optional</para></td>
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<td><para>True</para></td>
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<td><para>Enable mapping vdisks to multiple
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hosts <footnote
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xml:id="storwize-svc-fn9">
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<para>This option allows the driver
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to map a vdisk to more than one
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host at a time. This scenario
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occurs during migration of a
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virtual machine with an attached
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volume; the volume is
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simultaneously mapped to both the
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source and destination compute
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hosts. If your deployment does not
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require attaching vdisks to
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multiple hosts, setting this flag
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to False will provide added
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safety.</para>
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</footnote></para></td>
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</tr>
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</tbody>
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</table>
|
||
<xi:include
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||
href="../../../common/tables/cinder-storwize.xml"/>
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||
</simplesect>
|
||
<simplesect>
|
||
<title>Placement with volume types</title>
|
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<para>The IBM Storwize/SVC driver exposes capabilities
|
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that can be added to the <literal>extra
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specs</literal> of volume types, and used by the
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filter scheduler to determine placement of new
|
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volumes. Make sure to prefix these keys with
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<literal>capabilities:</literal> to indicate that
|
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the scheduler should use them. The following
|
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<literal>extra specs</literal> are
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supported:</para>
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<itemizedlist>
|
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<listitem>
|
||
<para>capabilities:volume_back-end_name - Specify
|
||
a specific back-end where the volume should be
|
||
created. The back-end name is a concatenation
|
||
of the name of the IBM Storwize/SVC storage
|
||
system as shown in
|
||
<literal>lssystem</literal>, an underscore,
|
||
and the name of the pool (mdisk group). For
|
||
example:
|
||
<programlisting>capabilities:volume_back-end_name=myV7000_openstackpool</programlisting></para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>capabilities:compression_support - Specify a
|
||
back-end according to compression support. A
|
||
value of <literal>True</literal> should be
|
||
used to request a back-end that supports
|
||
compression, and a value of
|
||
<literal>False</literal> will request a
|
||
back-end that does not support compression. If
|
||
you do not have constraints on compression
|
||
support, do not set this key. Note that
|
||
specifying <literal>True</literal> does not
|
||
enable compression; it only requests that the
|
||
volume be placed on a back-end that supports
|
||
compression. Example syntax:
|
||
<programlisting>capabilities:compression_support='<is> True'</programlisting></para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>capabilities:easytier_support - Similar
|
||
semantics as the
|
||
<literal>compression_support</literal>
|
||
key, but for specifying according to support
|
||
of the Easy Tier feature. Example syntax:
|
||
<programlisting>capabilities:easytier_support='<is> True'</programlisting></para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>capabilities:storage_protocol - Specifies
|
||
the connection protocol used to attach volumes
|
||
of this type to instances. Legal values are
|
||
<literal>iSCSI</literal> and
|
||
<literal>FC</literal>. This <literal>extra
|
||
specs</literal> value is used for both
|
||
placement and setting the protocol used for
|
||
this volume. In the example syntax, note
|
||
<in> is used as opposed to <is>
|
||
used in the previous examples.
|
||
<programlisting>capabilities:storage_protocol='<in> FC'</programlisting></para>
|
||
</listitem>
|
||
</itemizedlist>
|
||
</simplesect>
|
||
<simplesect>
|
||
<title>Configure per-volume creation options</title>
|
||
<para>Volume types can also be used to pass options to the
|
||
IBM Storwize/SVC driver, which over-ride the default
|
||
values set in the configuration file. Contrary to the
|
||
previous examples where the "capabilities" scope was
|
||
used to pass parameters to the Cinder scheduler,
|
||
options can be passed to the IBM Storwize/SVC driver
|
||
with the "drivers" scope.</para>
|
||
<para>The following <literal>extra specs</literal> keys
|
||
are supported by the IBM Storwize/SVC driver:</para>
|
||
<itemizedlist>
|
||
<listitem>
|
||
<para>rsize</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>warning</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>autoexpand</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>grainsize</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>compression</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>easytier</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>multipath</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>iogrp</para>
|
||
</listitem>
|
||
</itemizedlist>
|
||
<para>These keys have the same semantics as their
|
||
counterparts in the configuration file. They are set
|
||
similarly; for example, <literal>rsize=2</literal> or
|
||
<literal>compression=False</literal>.</para>
|
||
</simplesect>
|
||
<simplesect>
|
||
<title>Example: Volume types</title>
|
||
<para>In the following example, we create a volume type to
|
||
specify a controller that supports iSCSI and
|
||
compression, to use iSCSI when attaching the volume,
|
||
and to enable compression:</para>
|
||
<screen><prompt>$</prompt> <userinput>cinder type-create compressed</userinput>
|
||
<prompt>$</prompt> <userinput>cinder type-key compressed set capabilities:storage_protocol='<in> iSCSI' capabilities:compression_support='<is> True' drivers:compression=True</userinput></screen>
|
||
<para>We can then create a 50GB volume using this
|
||
type:</para>
|
||
<screen><prompt>$</prompt> <userinput>cinder create --display-name "compressed volume" --volume-type compressed 50</userinput></screen>
|
||
|
||
<para>Volume types can be used, for example, to provide
|
||
users with different</para>
|
||
<itemizedlist>
|
||
<listitem>
|
||
<para>performance levels (such as, allocating
|
||
entirely on an HDD tier, using Easy Tier for
|
||
an HDD-SDD mix, or allocating entirely on an
|
||
SSD tier)</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>resiliency levels (such as, allocating
|
||
volumes in pools with different RAID
|
||
levels)</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>features (such as, enabling/disabling
|
||
Real-time Compression)</para>
|
||
</listitem>
|
||
</itemizedlist>
|
||
</simplesect>
|
||
</section>
|
||
<section xml:id="ibm-storwize-svc-driver3">
|
||
<title>Operational notes for the Storwize family and SVC
|
||
driver</title>
|
||
<simplesect>
|
||
<title>Migrate volumes</title>
|
||
<para>In the context of OpenStack Block Storage's volume
|
||
migration feature, the IBM Storwize/SVC driver enables
|
||
the storage's virtualization technology. When
|
||
migrating a volume from one pool to another, the
|
||
volume will appear in the destination pool almost
|
||
immediately, while the storage moves the data in the
|
||
background.</para>
|
||
<note>
|
||
<para>To enable this feature, both pools involved in a
|
||
given volume migration must have the same values
|
||
for <literal>extent_size</literal>. If the pools
|
||
have different values for
|
||
<literal>extent_size</literal>, the data will
|
||
still be moved directly between the pools (not
|
||
host-side copy), but the operation will be
|
||
synchronous.</para>
|
||
</note>
|
||
</simplesect>
|
||
<simplesect>
|
||
<title>Extend volumes</title>
|
||
<para>The IBM Storwize/SVC driver allows for extending a
|
||
volume's size, but only for volumes without
|
||
snapshots.</para>
|
||
</simplesect>
|
||
<simplesect>
|
||
<title>Snapshots and clones</title>
|
||
<para>Snapshots are implemented using FlashCopy with no
|
||
background copy (space-efficient). Volume clones
|
||
(volumes created from existing volumes) are
|
||
implemented with FlashCopy, but with background copy
|
||
enabled. This means that volume clones are
|
||
independent, full copies. While this background copy
|
||
is taking place, attempting to delete or extend the
|
||
source volume will result in that operation waiting
|
||
for the copy to complete.</para>
|
||
</simplesect>
|
||
<simplesect>
|
||
<title>Volume retype</title>
|
||
<para>The IBM Storwize/SVC driver enables you to modify
|
||
volume types. When you modify volume types, you can
|
||
also change these extra specs properties:</para>
|
||
<itemizedlist>
|
||
<listitem>
|
||
<para>rsize</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>warning</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>autoexpand</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>grainsize</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>compression</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>easytier</para>
|
||
</listitem>
|
||
<listitem>
|
||
<para>iogrp</para>
|
||
</listitem>
|
||
</itemizedlist>
|
||
<note>
|
||
<para>When you change the <literal>rsize</literal>,
|
||
<literal>grainsize</literal> or
|
||
<literal>compression</literal> properties,
|
||
volume copies are asynchronously synchronized on
|
||
the array.</para>
|
||
</note>
|
||
<note>
|
||
<para>To change the <literal>iogrp</literal> property,
|
||
IBM Storwize/SVC firmware version 6.4.0 or later
|
||
is required.</para>
|
||
</note>
|
||
</simplesect>
|
||
</section>
|
||
</section>
|