You can manage instance types and instance flavors using the nova-manage command-line interface coupled with the instance_type subcommand for nova-manage.
Instance types describe the compute, memory and storage capacity of nova computing instances. In layman terms, this is the size (in terms of vCPUs, RAM, etc.) of the virtual server that you will be launching. In the EC2 API, these are called by names such as “m1.large” or “m1.tiny”, while the OpenStack API terms these “flavors” with names like “512 MB Server”.
In Nova, “flavor” and “instance type” are equivalent terms. When you create an EC2 instance type, you are also creating a OpenStack API flavor. To reduce repetition, for the rest of this document I will refer to these as instance types.
In the current (Cactus) version of nova, instance types can only be created by the nova administrator through the nova-manage command. Future versions of nova (in concert with the OpenStack API or EC2 API), may expose this functionality directly to users.
Instance types / flavor are managed through the nova-manage binary with the “instance_type” command and an appropriate subcommand. Note that you can also use the “flavor” command as a synonym for “instance_types”.
To see all currently active instance types, use the list subcommand:
# nova-manage instance_type list
m1.medium: Memory: 4096MB, VCPUS: 2, Storage: 40GB, FlavorID: 3, Swap: 0GB, RXTX Quota: 0GB, RXTX Cap: 0MB
m1.large: Memory: 8192MB, VCPUS: 4, Storage: 80GB, FlavorID: 4, Swap: 0GB, RXTX Quota: 0GB, RXTX Cap: 0MB
m1.tiny: Memory: 512MB, VCPUS: 1, Storage: 0GB, FlavorID: 1, Swap: 0GB, RXTX Quota: 0GB, RXTX Cap: 0MB
m1.xlarge: Memory: 16384MB, VCPUS: 8, Storage: 160GB, FlavorID: 5, Swap: 0GB, RXTX Quota: 0GB, RXTX Cap: 0MB
m1.small: Memory: 2048MB, VCPUS: 1, Storage: 20GB, FlavorID: 2, Swap: 0GB, RXTX Quota: 0GB, RXTX Cap: 0MB
By default, the list subcommand only shows active instance types. To see all instance types (inactive and active), use the list subcommand with the “–all” flag:
# nova-manage instance_type list --all
m1.medium: Memory: 4096MB, VCPUS: 2, Storage: 40GB, FlavorID: 3, Swap: 0GB, RXTX Quota: 0GB, RXTX Cap: 0MB
m1.large: Memory: 8192MB, VCPUS: 4, Storage: 80GB, FlavorID: 4, Swap: 0GB, RXTX Quota: 0GB, RXTX Cap: 0MB
m1.tiny: Memory: 512MB, VCPUS: 1, Storage: 0GB, FlavorID: 1, Swap: 0GB, RXTX Quota: 0GB, RXTX Cap: 0MB
m1.xlarge: Memory: 16384MB, VCPUS: 8, Storage: 160GB, FlavorID: 5, Swap: 0GB, RXTX Quota: 0GB, RXTX Cap: 0MB
m1.small: Memory: 2048MB, VCPUS: 1, Storage: 20GB, FlavorID: 2, Swap: 0GB, RXTX Quota: 0GB, RXTX Cap: 0MB
m1.deleted: Memory: 2048MB, VCPUS: 1, Storage: 20GB, FlavorID: 2, Swap: 0GB, RXTX Quota: 0GB, RXTX Cap: 0MB, inactive
The following example creates an instance type named “m1.xxlarge”:
# nova-manage instance_type create m1.xxlarge 32768 16 320 0 0 0
m1.xxlarge created
To delete an instance type, use the “delete” subcommand and specify the name:
# nova-manage instance_type delete m1.xxlarge
m1.xxlarge deleted
Please note that the “delete” command only marks the instance type as inactive in the database; it does not actually remove the instance type. This is done to preserve the instance type definition for long running instances (which may not terminate for months or years). If you are sure that you want to delete this instance type from the database, pass the “–purge” flag after the name:
# nova-manage instance_type delete m1.xxlarge --purge
m1.xxlarge purged