Launch an instance from a volume¶
You can boot instances from a volume instead of an image.
To complete these tasks, use these parameters on the nova boot command:
| Task | nova boot parameter | Information |
|---|---|---|
| Boot an instance from an image and attach a non-bootable volume. | --block-device | Boot instance from image and attach non-bootable volume |
| Create a volume from an image and boot an instance from that volume. | --block-device | Create volume from image and boot instance |
| Boot from an existing source image, volume, or snapshot. | --block-device | Create volume from image and boot instance |
| Attach a swap disk to an instance. | --swap | Attach swap or ephemeral disk to an instance |
| Attach an ephemeral disk to an instance. | --ephemeral | Attach swap or ephemeral disk to an instance |
Note
To attach a volume to a running instance, see Attach a volume to an instance.
Boot instance from image and attach non-bootable volume¶
Create a non-bootable volume and attach that volume to an instance that you boot from an image.
To create a non-bootable volume, do not create it from an image. The volume must be entirely empty with no partition table and no file system.
Create a non-bootable volume.
$ cinder create --display-name my-volume 8 +--------------------------------+--------------------------------------+ | Property | Value | +--------------------------------+--------------------------------------+ | attachments | [] | | availability_zone | nova | | bootable | false | | created_at | 2014-05-09T16:33:11.000000 | | description | None | | encrypted | False | | id | d620d971-b160-4c4e-8652-2513d74e2080 | | metadata | {} | | name | my-volume | | 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 | ccef9e62b1e645df98728fb2b3076f27 | | size | 8 | | snapshot_id | None | | source_volid | None | | status | creating | | user_id | fef060ae7bfd4024b3edb97dff59017a | | volume_type | None | +--------------------------------+--------------------------------------+
List volumes.
$ cinder list +-----------------+-----------+-----------+------+-------------+----------+-------------+ | ID | Status | Name | Size | Volume Type | Bootable | Attached to | +-----------------+-----------+-----------+------+-------------+----------+-------------+ | d620d971-b16... | available | my-volume | 8 | None | false | | +-----------------+-----------+-----------+------+-------------+----------+-------------+
Boot an instance from an image and attach the empty volume to the instance.
$ nova boot --flavor 2 --image 98901246-af91-43d8-b5e6-a4506aa8f369 \ --block-device source=volume,id=d620d971-b160-4c4e-8652-2513d74e2080,dest=volume,shutdown=preserve \ myInstanceWithVolume +--------------------------------------+--------------------------------------------+ | Property | Value | +--------------------------------------+--------------------------------------------+ | OS-DCF:diskConfig | MANUAL | | OS-EXT-AZ:availability_zone | nova | | OS-EXT-SRV-ATTR:host | - | | OS-EXT-SRV-ATTR:hypervisor_hostname | - | | OS-EXT-SRV-ATTR:instance_name | instance-00000004 | | OS-EXT-STS:power_state | 0 | | OS-EXT-STS:task_state | scheduling | | OS-EXT-STS:vm_state | building | | OS-SRV-USG:launched_at | - | | OS-SRV-USG:terminated_at | - | | accessIPv4 | | | accessIPv6 | | | adminPass | ZaiYeC8iucgU | | config_drive | | | created | 2014-05-09T16:34:50Z | | flavor | m1.small (2) | | hostId | | | id | 1e1797f3-1662-49ff-ae8c-a77e82ee1571 | | image | cirros-0.3.1-x86_64-uec (98901246-af91-... | | key_name | - | | metadata | {} | | name | myInstanceWithVolume | | os-extended-volumes:volumes_attached | [{"id": "d620d971-b160-4c4e-8652-2513d7... | | progress | 0 | | security_groups | default | | status | BUILD | | tenant_id | ccef9e62b1e645df98728fb2b3076f27 | | updated | 2014-05-09T16:34:51Z | | user_id | fef060ae7bfd4024b3edb97dff59017a | +--------------------------------------+--------------------------------------------+
Create volume from image and boot instance¶
You can create a volume from an existing image, volume, or snapshot. This procedure shows you how to create a volume from an image, and use the volume to boot an instance.
List the available images.
$ nova image-list +-----------------+---------------------------------+--------+--------+ | ID | Name | Status | Server | +-----------------+---------------------------------+--------+--------+ | 484e05af-a14... | Fedora-x86_64-20-20131211.1-sda | ACTIVE | | | 98901246-af9... | cirros-0.3.1-x86_64-uec | ACTIVE | | | b6e95589-7eb... | cirros-0.3.1-x86_64-uec-kernel | ACTIVE | | | c90893ea-e73... | cirros-0.3.1-x86_64-uec-ramdisk | ACTIVE | | +-----------------+---------------------------------+--------+--------+
Note the ID of the image that you want to use to create a volume.
If you want to create a volume to a specific storage backend, you need to use an image which has cinder_img_volume_type property. In this case, a new volume will be created as storage_backend1 volume type.
$ nova image-show 98901246-af9... +---------------------------------+--------------------------------------+ | Property | Value | +---------------------------------+--------------------------------------+ | OS-EXT-IMG-SIZE:size | 25165824 | | created | 2016-03-11T16:39:25Z | | id | 98901246-af9... | | metadata cinder_img_volume_type | storage_backend1 | | metadata kernel_id | 759e3e20-83b... | | metadata ramdisk_id | 5a8b526f-d5c... | | minDisk | 0 | | minRam | 0 | | name | cirros-0.3.4-x86_64-uec | | progress | 100 | | status | ACTIVE | | updated | 2016-03-17T22:55:03Z | +---------------------------------+--------------------------------------+
List the available flavors.
$ nova flavor-list +-----+-----------+-----------+------+-----------+------+-------+-------------+-----------+ | ID | Name | Memory_MB | Disk | Ephemeral | Swap | VCPUs | RXTX_Factor | Is_Public | +-----+-----------+-----------+------+-----------+------+-------+-------------+-----------+ | 1 | m1.tiny | 512 | 1 | 0 | | 1 | 1.0 | True | | 2 | m1.small | 2048 | 20 | 0 | | 1 | 1.0 | True | | 3 | m1.medium | 4096 | 40 | 0 | | 2 | 1.0 | True | | 4 | m1.large | 8192 | 80 | 0 | | 4 | 1.0 | True | | 5 | m1.xlarge | 16384 | 160 | 0 | | 8 | 1.0 | True | +-----+-----------+-----------+------+-----------+------+-------+-------------+-----------+
Note the ID of the flavor that you want to use to create a volume.
To create a bootable volume from an image and launch an instance from this volume, use the --block-device parameter.
For example:
$ nova boot --flavor FLAVOR --block-device \ source=SOURCE,id=ID,dest=DEST,size=SIZE,shutdown=PRESERVE,bootindex=INDEX \ NAME
The parameters are:
--flavor FLAVOR. The flavor ID or name.
--block-device source=SOURCE,id=ID,dest=DEST,size=SIZE,shutdown=PRESERVE,bootindex=INDEX
- source=SOURCE
The type of object used to create the block device. Valid values are volume, snapshot, image, and blank.
- id=ID
The ID of the source object.
- dest=DEST
The type of the target virtual device. Valid values are volume and local.
- size=SIZE
The size of the volume that is created.
- shutdown={preserve|remove}
What to do with the volume when the instance is deleted. preserve does not delete the volume. remove deletes the volume.
- bootindex=INDEX
Orders the boot disks. Use 0 to boot from this volume.
NAME. The name for the server.
Create a bootable volume from an image, before the instance boots. The volume is not deleted when the instance is terminated.
$ nova boot --flavor 2 \ --block-device source=image,id=484e05af-a14d-4567-812b-28122d1c2260,dest=volume,size=10,shutdown=preserve,bootindex=0 \ myInstanceFromVolume +--------------------------------------+--------------------------------+ | Property | Value | +--------------------------------------+--------------------------------+ | OS-EXT-STS:task_state | scheduling | | image | Attempt to boot from volume | | | - no image supplied | | OS-EXT-STS:vm_state | building | | OS-EXT-SRV-ATTR:instance_name | instance-00000003 | | OS-SRV-USG:launched_at | None | | flavor | m1.small | | id | 2e65c854-dba9-4f68-8f08-fe3... | | security_groups | [{u'name': u'default'}] | | user_id | 352b37f5c89144d4ad053413926... | | OS-DCF:diskConfig | MANUAL | | accessIPv4 | | | accessIPv6 | | | progress | 0 | | OS-EXT-STS:power_state | 0 | | OS-EXT-AZ:availability_zone | nova | | config_drive | | | status | BUILD | | updated | 2014-02-02T13:29:54Z | | hostId | | | OS-EXT-SRV-ATTR:host | None | | OS-SRV-USG:terminated_at | None | | key_name | None | | OS-EXT-SRV-ATTR:hypervisor_hostname | None | | name | myInstanceFromVolume | | adminPass | TzjqyGsRcJo9 | | tenant_id | f7ac731cc11f40efbc03a9f9e1d... | | created | 2014-02-02T13:29:53Z | | os-extended-volumes:volumes_attached | [] | | metadata | {} | +--------------------------------------+--------------------------------+
List volumes to see the bootable volume and its attached myInstanceFromVolume instance.
$ cinder list +-------------+--------+--------------+------+-------------+----------+-------------+ | ID | Status | Display Name | Size | Volume Type | Bootable | Attached to | +-------------+--------+--------------+------+-------------+----------+-------------+ | 2fff50ab... | in-use | | 10 | None | true | 2e65c854... | +-------------+--------+--------------+------+-------------+----------+-------------+
Attach swap or ephemeral disk to an instance¶
Use the nova boot --swap parameter to attach a swap disk on boot or the nova boot --ephemeral parameter to attach an ephemeral disk on boot. When you terminate the instance, both disks are deleted.
Boot an instance with a 512 MB swap disk and 2 GB ephemeral disk.
$ nova boot --flavor FLAVOR --image IMAGE_ID --swap 512 --ephemeral size=2 NAME
Note
The flavor defines the maximum swap and ephemeral disk size. You cannot exceed these maximum values.
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