############################
cinder连接LVM存储后端
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**Table of Contents:**

- 目标_
- 准备物理环境_
- 修改cinder配置文件_


目标
=======================

创建增加cinder volume时volume type

.. image::  _static/create_volume.png

::

  [root@overcloud-controller-0 cinder]# cinder type-list
  +--------------------------------------+--------------+--------------------------+-----------+
  |                  ID                  |     Name     |       Description        | Is_Public |
  +--------------------------------------+--------------+--------------------------+-----------+
  | 289f591e-59a9-4f93-9549-eb553941240b | tripleo-ceph |   ceph tripleo backend   |    True   |
  | d259562a-b958-4bb1-8149-15429ffd71af |  cinderlvm   | LVM test on controller-0 |   False   |
  +--------------------------------------+--------------+--------------------------+-----------+


准备物理环境
=======================
- 安装必要软件

::

  rpm -ivh perl-Config-General-2.61-1.el7.noarch.rpm
  rpm -ivh scsi-target-utils-1.0.55-4.el7.x86_64.rpm

- 创建loop设备

由于节点已经没有多余裸盘可以用，所以从controller-0划出一部分空间挂载为loop设备::

  dd if=/dev/zero of=/cinder-test.dontdelete bs=1 count=0 seek=100G
  losetup /dev/loop3 /var/lib/cinder/cinder-test.dontdelete

- 创建physical volume

::

  [root@overcloud-controller-0 cinder]#pvcreate /dev/loop3
  [root@overcloud-controller-0 cinder]#pvdisplay
  --- Physical volume ---
  PV Name               /dev/loop3
  VG Name               cinderlvm
  PV Size               100.00 GiB / not usable 4.00 MiB
  Allocatable           yes
  PE Size               4.00 MiB
  Total PE              25599
  Free PE               25599
  Allocated PE          0
  PV UUID               6Zpmmb-EjKi-PlHQ-ojon-9hJT-olHH-mMvhSW


- 创建volume group

::

  [root@overcloud-controller-0 cinder]#vgcreate cinderlvm /dev/loop3
  [root@overcloud-controller-0 cinder]#vgdisplay
  --- Volume group ---
  VG Name               cinderlvm
  System ID
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  3
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                0
  Open LV               0
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               100.00 GiB
  PE Size               4.00 MiB
  Total PE              25599
  Alloc PE / Size       0 / 0
  Free  PE / Size       25599 / 100.00 GiB
  VG UUID               AyVZbf-FAIY-agzq-Hd3O-j7cx-sdiy-X03NkO


修改cinder配置文件
====================================
- 查看当前配置

::

  [root@overcloud-controller-0 cinder]# crudini --get /etc/cinder/cinder.conf DEFAULT enabled_backends
  tripleo-ceph

- 增加存储后端

::

  [root@overcloud-controller-0 cinder]# crudini --set /etc/cinder/cinder.conf DEFAULT enabled_backends tripleo-ceph,lvmtest

- 在/etc/cinder/cinder.conf中增加lvmtest段落

::

  [lvmtest]   """对应[DEFAULT]段落中的enabled_backends"""
  volume_driver = cinder.volume.drivers.lvm.LVMVolumeDriver
  volume_group = cinderlvm
  iscsi_helper = tgtadm
  volume_backend_name = lvmtest-renbin

- 创建volume type

::

  [root@overcloud-controller-0 cinder]# cinder type-create cinderlvm
  [root@overcloud-controller-0 cinder]# cinder type-key cinderlvm set volume_backend_name=lvmtest-renbin
  [root@overcloud-controller-0 cinder]# cinder extra-specs-list
  +--------------------------------------+--------------+---------------------------------------------+
  |                  ID                  |     Name     |                 extra_specs                 |
  +--------------------------------------+--------------+---------------------------------------------+
  | 289f591e-59a9-4f93-9549-eb553941240b | tripleo-ceph |  {u'volume_backend_name': u'tripleo-ceph'}  |
  | d259562a-b958-4bb1-8149-15429ffd71af |  cinderlvm   | {u'volume_backend_name': u'lvmtest-renbin'} |
  +--------------------------------------+--------------+---------------------------------------------+

- 重启cinder服务

::

  [root@overcloud-controller-0 cinder]#pcs resource restart openstack-cinder-scheduler-clone
  [root@overcloud-controller-0 cinder]#pcs resource restart openstack-cinder-api-clone
  [root@overcloud-controller-0 cinder]#pcs resource restart openstack-cinder-volume

- 测试创建volume

::


  [root@overcloud-controller-0 cinder]# cinder create --name testlvm --volume-type cinderlvm 10
  +---------------------------------------+--------------------------------------+
  |                Property               |                Value                 |
  +---------------------------------------+--------------------------------------+
  |              attachments              |                  []                  |
  |           availability_zone           |                 nova                 |
  |                bootable               |                false                 |
  |          consistencygroup_id          |                 None                 |
  |               created_at              |      2018-01-19T06:46:37.000000      |
  |              description              |                 None                 |
  |               encrypted               |                False                 |
  |                   id                  | c4b247a8-9808-4bcf-a7b2-080b4cc2b0f9 |
  |                metadata               |                  {}                  |
  |            migration_status           |                 None                 |
  |              multiattach              |                False                 |
  |                  name                 |               testlvm                |
  |         os-vol-host-attr:host         |                 None                 |
  |     os-vol-mig-status-attr:migstat    |                 None                 |
  |     os-vol-mig-status-attr:name_id    |                 None                 |
  |      os-vol-tenant-attr:tenant_id     |   dcbb3cd11f48438383d6232af95b7d93   |
  |   os-volume-replication:driver_data   |                 None                 |
  | os-volume-replication:extended_status |                 None                 |
  |           replication_status          |               disabled               |
  |                  size                 |                  10                  |
  |              snapshot_id              |                 None                 |
  |              source_volid             |                 None                 |
  |                 status                |               creating               |
  |                user_id                |   1c3c35d5e1bb4c8c8d78c276661af2a9   |
  |              volume_type              |              cinderlvm               |
  +---------------------------------------+--------------------------------------+