649 lines
32 KiB
XML
649 lines
32 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"
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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
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SAN Volume Controller (SVC) provides OpenStack Compute
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instances with access to IBM Storwize family or SVC
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storage systems.</para>
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<section xml:id="ibm-storwize-svc-driver1">
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<title>Configuring 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
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configured for iSCSI, Fibre Channel, or both.</para>
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<para>If using iSCSI, each Storwize family or SVC node should
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have at least one iSCSI IP address.
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The IBM Storwize/SVC driver uses an iSCSI IP address associated
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with the volume's preferred
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node (if available) to attach the volume to the
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instance, otherwise it uses the first available
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iSCSI IP address of the system.
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The driver obtains the iSCSI IP address
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directly from the storage system;
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there is no need to provide these
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iSCSI IP addresses directly to the 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.
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Once this is configured on the Nova host (outside the
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scope of this documentation), multipath is enabled.
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</para>
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</note>
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<para>If using Fibre Channel (FC), each Storwize family or SVC
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node should have at least one WWPN port configured.
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If the <literal>storwize_svc_multipath_enabled</literal> flag
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is set to True in the Cinder configuration file, the driver
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uses all available WWPNs to attach the volume to the
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instance (details about the configuration flags appear in the
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<link linkend="ibm-storwize-svc-driver2"> next section</link>).
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If the flag is not set, the driver uses the WWPN
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associated with the volume's preferred node (if available),
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otherwise it uses the first available WWPN of the system.
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The driver obtains the WWPNs directly from the storage system;
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there is no need to provide these WWPNs directly to the driver.
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</para>
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<note>
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<para>If using FC, ensure that the compute nodes
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have FC connectivity to the Storwize family
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or SVC 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, all new hosts created by
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the driver on the Storwize family or SVC system has a
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randomly-generated CHAP secret associated with them.
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OpenStack compute nodes use these secrets when creating
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iSCSI connections.
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<note>
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<para>CHAP secrets are not added to existing
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hosts.</para>
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</note>
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<note>
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<para>CHAP secrets are passed from Cinder to Nova
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in clear text. This communication should be
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secured to ensure that CHAP secrets are not
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discovered.</para>
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</note>
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</para>
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</simplesect>
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<simplesect>
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<title>Configuring storage pools</title>
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<para>Each instance of the IBM Storwize/SVC driver allocates
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all volumes in a single pool.
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The pool should be created in advance and be
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provided to the driver using the
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<literal>storwize_svc_volpool_name</literal>
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configuration flag.
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Details about the configuration flags and how
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to provide the flags to the driver appear in the
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<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>Configuring user authentication for the driver
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</title>
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<para>The driver requires access to the Storwize
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family or SVC system management interface.
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The driver communicates with
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the management using SSH.
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The driver should be provided with the Storwize
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family or SVC management IP using the
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<literal>san_ip</literal>
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flag, and the management port should be
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provided by the
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<literal>san_ssh_port</literal> flag.
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By default, the port value is configured to
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be port 22 (SSH).</para>
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<note>
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<para>Make sure the compute node running
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the nova-volume management driver has SSH
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network access to
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the storage system.</para>
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</note>
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<para>To allow the driver to communicate with the
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Storwize family or SVC system,
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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
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authentication and SSH key pair authentication.
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The user should have an Administrator role.
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It is suggested to create a new
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user for the management driver.
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Please consult with your
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storage and security administrator regarding
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the preferred authentication method and how
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passwords or SSH keys should be stored in a
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secure manner.</para>
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<note>
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<para>When creating a new user on the Storwize or
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SVC system, make sure the user belongs to
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the Administrator group or to another group
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that has an Administrator role.</para>
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</note>
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<para>If using password authentication, assign a
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password to the user on the Storwize or SVC
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system.
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The driver configuration flags for the user and
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password are <literal>san_login</literal> and
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<literal>san_password</literal>, respectively.
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</para>
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<para>If you are using the SSH key pair
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authentication, create SSH
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private and public keys using the instructions
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below or by any other method.
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Associate the public key with the
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user by uploading the public key: select the
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"choose file" option in the Storwize family or
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SVC management GUI under "SSH public key".
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Alternatively, you may associate the SSH public
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key using the command line interface;
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details can be found in the
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Storwize and SVC documentation.
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The private key should
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be provided to the driver using the
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<literal>san_private_key</literal>
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configuration flag.</para>
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</simplesect>
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<simplesect>
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<title>Creating a SSH key pair using OpenSSH</title>
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<para>You can create an SSH key pair using OpenSSH,
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by running:
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</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
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pair.
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For example, if you select 'key' as the
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filename, two files are created:
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<literal>key</literal> and
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<literal>key.pub</literal>.
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The <literal>key</literal>
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file holds the private SSH key and
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<literal>key.pub</literal> holds the public
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SSH key.
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</para>
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<para>The command also prompts for a pass phrase,
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which 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
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<literal>san_private_key</literal>
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configuration flag. The public key should be
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uploaded to the Storwize family or SVC system
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using the storage management GUI or command
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line interface.</para>
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<note>
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<para>Ensure that Cinder has read permissions on
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the 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>Configuring the Storwize Family and SVC Driver</title>
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<simplesect>
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<title>Enabling the Storwize family and SVC driver
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</title>
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<para>Set the volume driver to the Storwize family and
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SVC driver by setting the
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<literal>volume_driver</literal> option in
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<filename>cinder.conf</filename> as follows:</para>
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<programlisting>volume_driver = cinder.volume.drivers.storwize_svc.StorwizeSVCDriver</programlisting>
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</simplesect>
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<simplesect>
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<title>Configuring options for the Storwize family and
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SVC driver in cinder.conf</title>
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<para>The following options specify default values for all
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volumes.
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Some can be over-ridden using volume types, which
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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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<td>Flag name</td>
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<td>Type</td>
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<td>Default</td>
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<td>Description</td>
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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></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>
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</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></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>
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</para>
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</td>
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<td><para>Required
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<footnote xml:id='storwize-svc-fn1'>
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<para>The authentication requires either a
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password
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(<literal>san_password</literal>) or
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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.
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</para></footnote>
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</para></td>
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<td><para></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>
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</para>
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</td>
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<td><para>Required
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<footnoteref linkend='storwize-svc-fn1'/>
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</para></td>
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<td><para></para></td>
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<td><para>Management login SSH private key
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</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>
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</para>
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</td>
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<td><para>Required</para></td>
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<td><para></para></td>
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<td><para>Default pool name for 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>
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</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 (percentage)
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<footnote xml:id='storwize-svc-fn3'>
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<para>
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The driver creates thin-provisioned
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volumes by 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 thin-provisioned
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volumes, or if set to
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<literal>-1</literal>,
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the driver creates full allocated
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volumes. More details
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about the available options are available
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in the Storwize family and SVC
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documentation.
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</para></footnote>
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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_warning</literal>
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</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)
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<footnoteref 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>
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</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>
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Defines whether thin-provisioned volumes
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can be auto expanded by the storage
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system, a value of <literal>True</literal>
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means that auto expansion is
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enabled, a value of
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<literal>False</literal>
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disables auto expansion.
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Details about this option can be
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found in the
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<literal>–autoexpand</literal>
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flag of the Storwize
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family and SVC command line interface
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<literal>mkvdisk</literal> command.
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</para></footnote>
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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_grainsize</literal>
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</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
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<footnoteref linkend='storwize-svc-fn3'/>
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in 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>
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</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>
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Enable or disable Real-time Compression
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<footnote xml:id='storwize-svc-fn5'>
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<para>Defines whether Real-time Compression
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is used for the volumes created with
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OpenStack. Details on Real-time
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Compression can be found in the
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Storwize family and SVC documentation.
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The Storwize or SVC system must have
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compression enabled for this feature
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to work.
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</para>
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</footnote>
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</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>
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</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 used
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for the volumes created with OpenStack.
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Details on EasyTier can be found in the
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Storwize family and SVC documentation.
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The Storwize or SVC system must have
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Easy Tier enabled for this feature to
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work.
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</para></footnote>
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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_iogrp</literal>
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</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 vdisks
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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_flashcopy_timeout
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</literal>
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</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 threshold
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when creating an OpenStack
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snapshot. This is actually the
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maximum amount of time that the driver
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waits for the Storwize family
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or SVC system to prepare a new
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FlashCopy mapping. The driver
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accepts a maximum wait time of 600
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seconds (10 minutes).</para></footnote>
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(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>
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</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 (currently
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supports 'iSCSI' or 'FC')
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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_multipath_enabled
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</literal>
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</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 connections requires no
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storage-side configuration and is enabled
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if the compute host has multipath configured.
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</para></footnote>
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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_multihost_enabled
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</literal>
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</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 hosts
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<footnote xml:id='storwize-svc-fn9'>
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<para>This option allows the driver to map a vdisk
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to more than one host at a time. This scenario
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occurs during migration of a virtual machine
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with an attached volume; the volume is
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simultaneously mapped to both the source and
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destination compute hosts. If your deployment
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does not require attaching vdisks to multiple
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hosts, setting this flag to False will provide
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added safety.
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</para></footnote>
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</para></td>
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</tr>
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</tbody>
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</table>
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</simplesect>
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||
<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 specs</literal>
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of volume types, and used by the filter scheduler to
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determine placement of new volumes. Make sure to prefix
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these keys with <literal>capabilities:</literal> to
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indicate that the scheduler should use them. The following
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<literal>extra specs</literal> are supported:</para>
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|
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<itemizedlist>
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<listitem><para>capabilities:volume_backend_name - Specify
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a specific backend where the volume should be created. The
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backend name is a concatenation of the name of the
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||
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_backend_name=myV7000_openstackpool</programlisting>
|
||
</para></listitem>
|
||
|
||
<listitem><para>capabilities:compression_support - Specify
|
||
a backend according to compression support. A value of
|
||
<literal>True</literal> should be used to request a backend
|
||
that supports compression, and a value of
|
||
<literal>False</literal> will request a backend 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 backend 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>Configuring 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:
|
||
<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>
|
||
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 using 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
|
||
<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>
|
||
</para>
|
||
</simplesect>
|
||
</section>
|
||
<section xml:id="ibm-storwize-svc-driver3">
|
||
<title>Operational Notes for the Storwize Family and SVC Driver</title>
|
||
<simplesect>
|
||
<title>Volume Migration</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>Extending 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>
|
||
|
||
</section>
|
||
</section>
|