Compute
To use the information in this section, you must be familiar with OpenStack Compute.
Set environment variables
To set up environmental variables and authenticate
against Compute API endpoints, see .
Get OpenStack credentials (API v2)
These example use the
get_nova_credentials_v2 method:
def get_nova_credentials_v2():
d = {}
d['version'] = '2'
d['username'] = os.environ['OS_USERNAME']
d['api_key'] = os.environ['OS_PASSWORD']
d['auth_url'] = os.environ['OS_AUTH_URL']
d['project_id'] = os.environ['OS_TENANT_NAME']
return d
This code resides in the
credentials.py file, which all
samples import.
Use the get_nova_credentials_v2() method to
populate and get a dictionary:
credentials = get_nova_credentials_v2()
List servers (API v2)
The following program lists servers by using the Compute
API v2.
To list servers
Import the following modules:
from credentials import get_nova_credentials_v2
from novaclient.client import Client
Get Nova credentials. See .
Instantiate the nova_client
client object by using the
credentials dictionary
object:
nova_client = Client(**credentials)
List servers by calling
servers.list on
nova_client object:
print(nova_client.servers.list())
List servers code listing
#!/usr/bin/env python
from credentials import get_nova_credentials_v2
from novaclient.client import Client
credentials = get_nova_credentials_v2()
nova_client = Client(**credentials)
print(nova_client.servers.list())
Create server (API v2)
The following program creates a server (VM) by using the
Compute API v2.
To create a server
Import the following modules:
import time
from credentials import get_nova_credentials_v2
from novaclient.client import Client
Get OpenStack credentials. See .
Instantiate the nova_client
client object by using the
credentials dictionary
object:
nova_client = Client(**credentials)
Get the flavor and image to use to create a
server. This code uses the
cirros image, the
m1.tiny flavor, and the
private network:
image = nova_client.images.find(name="cirros")
flavor = nova_client.flavors.find(name="m1.tiny")
net = nova_client.networks.find(label="private")
To create the server, use the network, image, and
flavor:
nics = [{'net-id': net.id}]
instance = nova_client.servers.create(name="vm2", image=image,
flavor=flavor, key_name="keypair-1", nics=nics)
Sleep for five seconds and determine whether the
server/vm was created by calling
nova_client.servers.list():
print("Sleeping for 5s after create command")
time.sleep(5)
print("List of VMs")
print(nova_client.servers.list())
Create server code listing
#!/usr/bin/env python
import time
from credentials import get_nova_credentials_v2
from novaclient.client import Client
try:
credentials = get_nova_credentials_v2()
nova_client = Client(**credentials)
image = nova_client.images.find(name="cirros")
flavor = nova_client.flavors.find(name="m1.tiny")
net = nova_client.networks.find(label="private")
nics = [{'net-id': net.id}]
instance = nova_client.servers.create(name="vm2", image=image,
flavor=flavor, key_name="keypair-1", nics=nics)
print("Sleeping for 5s after create command")
time.sleep(5)
print("List of VMs")
print(nova_client.servers.list())
finally:
print("Execution Completed")
Delete server (API v2)
The following program deletes a server (VM) by using the
Compute API v2.
To delete a server
Import the following modules:
import time
from credentials import get_nova_credentials_v2
from novaclient.client import Client
Get Nova credentials. See .
Instantiate the nova_client
client object by using the
credentials dictionary
object:
nova_client = Client(**credentials)
Determine whether the vm1
server exists:
List servers:
servers_list.
Iterate over
servers_list and
compare name with
vm1.
If true, set the variable name
server_exists to
True and break from
the for loop:
servers_list = nova_client.servers.list()
server_del = "vm1"
server_exists = False
for s in servers_list:
if s.name == server_del:
print("This server %s exists" % server_del)
server_exists = True
break
If the server exists, run the
delete method of the
nova_client.servers
object:
nova_client.servers.delete(s)
Delete server code listing
#!/usr/bin/env python
from credentials import get_nova_credentials_v2
from novaclient.client import Client
credentials = get_nova_credentials_v2()
nova_client = Client(**credentials)
servers_list = nova_client.servers.list()
server_del = "vm1"
server_exists = False
for s in servers_list:
if s.name == server_del:
print("This server %s exists" % server_del)
server_exists = True
break
if not server_exists:
print("server %s does not exist" % server_del)
else:
print("deleting server..........")
nova_client.servers.delete(s)
print("server %s deleted" % server_del)
Update server (API v2)
The following program updates the name of a server (VM)
by using the Compute API v2.
To update a server
Import the following modules:
from credentials import get_nova_credentials_v2
from novaclient.client import Client
from utils import print_server
print_server is a method
defined in utils.py and
prints the server details as shown in the code
listing below:
def print_server(server):
print("-"*35)
print("server id: %s" % server.id)
print("server name: %s" % server.name)
print("server image: %s" % server.image)
print("server flavor: %s" % server.flavor)
print("server key name: %s" % server.key_name)
print("user_id: %s" % server.user_id)
print("-"*35)
Get OpenStack Credentials. See .
Instantiate the nova_client
client object by using the
credentials dictionary
object:
nova_client = Client(**credentials)
Get the server instance using
server_id and print the
details by calling print_server
method:
server_id = '99889c8d-113f-4a7e-970c-77f1916bfe14'
server = nova_client.servers.get(server_id)
n = server.name
print_server(server)
Call server.update on the server
object with the new value for
name variable:
server.update(name = n + '1')
Get the updated instance of the server:
server_updated = nova_client.servers.get(server_id)
Call print_server again to
check the update server details:
print_server(server_updated)
Update server code listing
#!/usr/bin/env python
from credentials import get_nova_credentials_v2
from novaclient.client import Client
from utils import print_server
credentials = get_nova_credentials_v2()
nova_client = Client(**credentials)
# Change the server_id specific to your environment
server_id = '99889c8d-113f-4a7e-970c-77f1916bfe14'
server = nova_client.servers.get(server_id)
n = server.name
print_server(server)
server.update(name=n +'1')
server_updated = nova_client.servers.get(server_id)
print_server(server_updated)
List flavors (API v2)
The following program lists flavors and their details by
using the Compute API v2.
To list flavors
Import the following modules:
from credentials import get_nova_credentials_v2
from novaclient.client import Client
from utils import print_flavors
The print_flavors method is
defined in utils.py and
prints the flavor details:
def print_flavors(flavor_list):
for flavor in flavor_list:
print("-"*35)
print("flavor id : %s" % flavor.id)
print("flavor name : %s" % flavor.name)
print("-"*35)
Get OpenStack credentials. See .
Instantiate the nova_client
client object by using the
credentials dictionary
object:
nova_client = Client(**credentials)
List flavors by calling
list() on
nova_client.flavors
object:
flavors_list = nova_client.flavors.list()
Print the flavor details, id and name by calling
print_flavors:
print_flavors(flavors_list)
List flavors code listing
#!/usr/bin/env python
from credentials import get_nova_credentials_v2
from novaclient.client import Client
from utils import print_flavors
credentials = get_nova_credentials_v2()
nova_client = Client(**credentials)
flavors_list = nova_client.flavors.list()
print_flavors(flavors_list)
List floating IPs (API v2)
The following program lists the floating IPs and their
details by using the Compute API v2.
To list floating IPs
Import the following modules:
from credentials import get_nova_credentials_v2
from novaclient.client import Client
from utils import print_values_ip
The print_values_ip method is
defined in utils.py and
prints the floating_ip object details:
def print_values_ip(ip_list):
ip_dict_lisl = []
for ip in ip_list:
print("-"*35)
print("fixed_ip : %s" % ip.fixed_ip)
print("id : %s" % ip.id)
print("instance_id : %s" % ip.instance_id)
print("ip : %s" % ip.ip)
print("pool : %s" % ip.pool)
Get OpenStack credentials. See .
Instantiate the nova_client
client object by using the
credentials dictionary
object:
nova_client = Client(**credentials)
List floating IPs by calling
list() on
nova_client.floating_ips
object:
ip_list = nova_client.floating_ips.list()
Print the floating IP object details by calling
print_values_ip:
print_values_ip(ip_list)
List floating IPs code listing
#!/usr/bin/env python
from credentials import get_nova_credentials_v2
from novaclient.client import Client
from utils import print_values_ip
credentials = get_nova_credentials_v2()
nova_client = Client(**credentials)
ip_list = nova_client.floating_ips.list()
print_values_ip(ip_list)
List hosts (API v2)
The following program lists the hosts by
using the Compute API v2.
To list hosts
Import the following modules:
from credentials import get_nova_credentials_v2
from novaclient.client import Client
from utils import print_hosts
The print_hosts method is
defined in utils.py and
prints the host object details:
def print_hosts(host_list):
for host in host_list:
print("-"*35)
print("host_name : %s" % host.host_name)
print("service : %s" % host.service)
print("zone : %s" % host.zone)
print("-"*35)
Get OpenStack credentials. See .
Instantiate the nova_client
client object by using the
credentials dictionary
object:
nova_client = Client(**credentials)
List hosts by calling list()
on nova_client.hosts
object:
host_list = nova_client.hosts.list()
Print the host object details by calling
print_hosts(host_list):
print_hosts(host_list)
List hosts code listing
#!/usr/bin/env python
from credentials import get_nova_credentials_v2
from novaclient.client import Client
from utils import print_hosts
credentials = get_nova_credentials_v2()
nova_client = Client(**credentials)
host_list = nova_client.hosts.list()
print_hosts(host_list)