有些东西记在这里，方便自己也方便他人。
nova help
usage: nova [--username USERNAME] [--apikey APIKEY] [--projectid PROJECTID]
[--url URL] [--region_name REGION_NAME] [--version VERSION]
<subcommand> ...
Command-line interface to the OpenStack Nova API.
Positional arguments:
<subcommand>
actions Retrieve server actions.
add-fixed-ip Add new IP address to network.
backup Backup a server.
backup-schedule Show or edit the backup schedule for a server.
backup-schedule-delete
Delete the backup schedule for a server.
boot Boot a new server.
boot-for-account Boot a new server in an account.
delete Immediately shut down and delete a server.
diagnostics Retrieve server diagnostics.
flavor-list Print a list of available 'flavors' (sizes of
servers).
image-create Create a new image by taking a snapshot of a running
server.
image-delete Delete an image.
image-list Print a list of available images to boot from.
ip-share Share an IP address from the given IP group onto a
server.
ip-unshare Stop sharing an given address with a server.
ipgroup-create Create a new IP group.
ipgroup-delete Delete an IP group.
ipgroup-list Show IP groups.
ipgroup-show Show details about a particular IP group.
list List active servers.
migrate Migrate a server.
pause Pause a server.
reboot Reboot a server.
rebuild Shutdown, re-image, and re-boot a server.
remove-fixed-ip Remove an IP address from a server.
rename Rename a server.
rescue Rescue a server.
resize Resize a server.
resize-confirm Confirm a previous resize.
resize-revert Revert a previous resize (and return to the previous
VM).
resume Resume a server.
root-password Change the root password for a server.
show Show details about the given server.
suspend Suspend a server.
unpause Unpause a server.
unrescue Unrescue a server.
zone Show or edit a child zone. No zone arg for this zone.
zone-add Add a new child zone.
zone-boot Boot a new server, potentially across Zones.
zone-delete Delete a zone.
zone-info Get this zones name and capabilities.
zone-list List the children of a zone.
help Display help about this program or one of its
subcommands.
Optional arguments:
--username USERNAME Defaults to env[NOVA_USERNAME].
--apikey APIKEY Defaults to env[NOVA_API_KEY].
--projectid PROJECTID
Defaults to env[NOVA_PROJECT_ID].
--url URL Defaults to env[NOVA_URL].
--region_name REGION_NAME
Defaults to env[NOVA_REGION_NAME].
--version VERSION Accepts 1.0 or 1.1, defaults to env[NOVA_VERSION].
See "nova help COMMAND" for help on a specific command.
