def add_to_load_balancer(log, endpoint, auth_token, lb_config, ip_address, undo, clock=None):
"""
Add an IP addressed to a load balancer based on the lb_config.
TODO: Handle load balancer node metadata.
:param log: A bound logger
:param str endpoint: Load balancer endpoint URI.
:param str auth_token: Keystone Auth Token.
:param str lb_config: An lb_config dictionary.
:param str ip_address: The IP Address of the node to add to the load
balancer.
:param IUndoStack undo: An IUndoStack to push any reversable operations onto.
:return: Deferred that fires with the Add Node to load balancer response
as a dict.
"""
lb_id = lb_config['loadBalancerId']
port = lb_config['port']
path = append_segments(endpoint, 'loadbalancers', str(lb_id), 'nodes')
lb_log = log.bind(loadbalancer_id=lb_id, ip_address=ip_address)
def add():
d = treq.post(path, headers=headers(auth_token),
data=json.dumps({"nodes": [{"address": ip_address,
"port": port,
"condition": "ENABLED",
"type": "PRIMARY"}]}),
log=lb_log)
d.addCallback(check_success, [200, 202])
d.addErrback(log_lb_unexpected_errors, lb_log, 'add_node')
d.addErrback(wrap_request_error, path, 'add_node')
d.addErrback(check_deleted_clb, lb_id)
return d
d = retry(
add,
can_retry=compose_retries(
transient_errors_except(CLBOrNodeDeleted),
retry_times(config_value('worker.lb_max_retries') or LB_MAX_RETRIES)),
next_interval=random_interval(
*(config_value('worker.lb_retry_interval_range') or LB_RETRY_INTERVAL_RANGE)),
clock=clock)
def when_done(result):
lb_log.msg('Added to load balancer', node_id=result['nodes'][0]['id'])
undo.push(remove_from_load_balancer,
lb_log,
endpoint,
auth_token,
lb_id,
result['nodes'][0]['id'])
return result
return d.addCallback(treq.json_content).addCallback(when_done)
def test_compose_retries(self):
"""
`compose_retries` returns True only if all its function returns True
"""
f1 = lambda f: f % 2 == 0
f2 = lambda f: f % 5 == 0
can_retry = compose_retries(f1, f2)
# True only if both f1 and f2 return True
self.assertTrue(can_retry(10))
# False otherwise
self.assertFalse(can_retry(8))
self.assertFalse(can_retry(3))
def test_compose_retries(self):
"""
`compose_retries` returns True only if all its function returns True
"""
f1 = lambda f: f % 2 == 0
f2 = lambda f: f % 5 == 0
can_retry = compose_retries(f1, f2)
# True only if both f1 and f2 return True
self.assertTrue(can_retry(10))
# False otherwise
self.assertFalse(can_retry(8))
self.assertFalse(can_retry(3))
def add_event(event, admin_tenant_id, region, log):
"""
Add event to cloud feeds
"""
event, error, timestamp, event_tenant_id, event_id = sanitize_event(event)
req = prepare_request(request_format, event, error, timestamp, region, event_tenant_id, event_id)
eff = retry_effect(
publish_autoscale_event(req, log=log),
compose_retries(lambda f: (not f.check(APIError) or f.value.code < 400 or f.value.code >= 500), retry_times(5)),
exponential_backoff_interval(2),
)
return Effect(TenantScope(tenant_id=admin_tenant_id, effect=eff))
def _remove_from_clb(log,
endpoint,
auth_token,
loadbalancer_id,
node_id,
clock=None):
"""
Remove a node from a CLB load balancer.
:param str endpoint: Load balancer endpoint URI.
:param str auth_token: Keystone authentication token.
:param str loadbalancer_id: The ID for a Cloud Load Balancer.
:param str node_id: The ID for a node in that Cloud Load Balancer.
:returns: A Deferred that fires with None if the operation completed successfully,
or errbacks with an RequestError.
"""
lb_log = log.bind(loadbalancer_id=loadbalancer_id, node_id=node_id)
# TODO: Will remove this once LB ERROR state is fixed and it is working fine
lb_log.msg('Removing from load balancer')
path = append_segments(endpoint, 'loadbalancers', str(loadbalancer_id),
'nodes', str(node_id))
def remove():
d = treq.delete(path, headers=headers(auth_token), log=lb_log)
d.addCallback(check_success, [200, 202])
d.addCallback(treq.content
) # To avoid https://twistedmatrix.com/trac/ticket/6751
d.addErrback(log_lb_unexpected_errors, lb_log, 'remove_node')
d.addErrback(wrap_request_error, path, 'remove_node')
d.addErrback(check_deleted_clb, loadbalancer_id, node_id)
return d
d = retry(remove,
can_retry=compose_retries(
transient_errors_except(CLBOrNodeDeleted),
retry_times(
config_value('worker.lb_max_retries')
or LB_MAX_RETRIES)),
next_interval=random_interval(
*(config_value('worker.lb_retry_interval_range')
or LB_RETRY_INTERVAL_RANGE)),
clock=clock)
# A node or CLB deleted is considered successful removal
d.addErrback(
lambda f: f.trap(CLBOrNodeDeleted) and lb_log.msg(f.value.message))
d.addCallback(lambda _: lb_log.msg('Removed from load balancer'))
return d
def add_event(event, admin_tenant_id, region, log):
"""
Add event to cloud feeds
"""
event, error, timestamp, event_tenant_id, event_id = sanitize_event(event)
req = prepare_request(request_format, event, error, timestamp, region,
event_tenant_id, event_id)
eff = retry_effect(
publish_autoscale_event(req, log=log),
compose_retries(
lambda f: (not f.check(APIError) or
f.value.code < 400 or
f.value.code >= 500),
retry_times(5)),
exponential_backoff_interval(2))
return Effect(TenantScope(tenant_id=admin_tenant_id, effect=eff))
def remove_from_load_balancer(log, endpoint, auth_token, loadbalancer_id,
node_id, clock=None):
"""
Remove a node from a load balancer.
:param str endpoint: Load balancer endpoint URI.
:param str auth_token: Keystone Auth Token.
:param str loadbalancer_id: The ID for a cloud loadbalancer.
:param str node_id: The ID for a node in that cloudloadbalancer.
:returns: A Deferred that fires with None if the operation completed successfully,
or errbacks with an RequestError.
"""
lb_log = log.bind(loadbalancer_id=loadbalancer_id, node_id=node_id)
# TODO: Will remove this once LB ERROR state is fixed and it is working fine
lb_log.msg('Removing from load balancer')
path = append_segments(endpoint, 'loadbalancers', str(loadbalancer_id), 'nodes', str(node_id))
def remove():
d = treq.delete(path, headers=headers(auth_token), log=lb_log)
d.addCallback(check_success, [200, 202])
d.addCallback(treq.content) # To avoid https://twistedmatrix.com/trac/ticket/6751
d.addErrback(log_lb_unexpected_errors, lb_log, 'remove_node')
d.addErrback(wrap_request_error, path, 'remove_node')
d.addErrback(check_deleted_clb, loadbalancer_id, node_id)
return d
d = retry(
remove,
can_retry=compose_retries(
transient_errors_except(CLBOrNodeDeleted),
retry_times(config_value('worker.lb_max_retries') or LB_MAX_RETRIES)),
next_interval=random_interval(
*(config_value('worker.lb_retry_interval_range') or LB_RETRY_INTERVAL_RANGE)),
clock=clock)
# A node or CLB deleted is considered successful removal
d.addErrback(lambda f: f.trap(CLBOrNodeDeleted) and lb_log.msg(f.value.message))
d.addCallback(lambda _: lb_log.msg('Removed from load balancer'))
return d
def launch_server(log,
request_bag,
scaling_group,
launch_config,
undo,
clock=None):
"""
Launch a new server given the launch config auth tokens and service
catalog. Possibly adding the newly launched server to a load balancer.
:param BoundLog log: A bound logger.
:param request_bag: An object with a bunch of useful data on it, including
a callable to re-auth and get a new token.
:param IScalingGroup scaling_group: The scaling group to add the launched
server to.
:param dict launch_config: A launch_config args structure as defined for
the launch_server_v1 type.
:param IUndoStack undo: The stack that will be rewound if undo fails.
:return: Deferred that fires with a 2-tuple of server details and the
list of load balancer responses from add_to_load_balancers.
"""
launch_config = prepare_launch_config(scaling_group.uuid, launch_config)
cloudServersOpenStack = config_value('cloudServersOpenStack')
server_endpoint = public_endpoint_url(request_bag.service_catalog,
cloudServersOpenStack,
request_bag.region)
lb_config = launch_config.get('loadBalancers', [])
server_config = launch_config['server']
log = log.bind(server_name=server_config['name'])
ilog = [None]
def check_metadata(server):
# sanity check to make sure the metadata didn't change - can probably
# be removed after a while if we do not see any log messages from this
# function
expected = launch_config['server']['metadata']
result = server['server'].get('metadata')
if result != expected:
ilog[0].msg('Server metadata has changed.',
sanity_check=True,
expected_metadata=expected,
nova_metadata=result)
return server
def wait_for_server(server, new_request_bag):
server_id = server['server']['id']
# NOTE: If server create is retried, each server delete will be pushed
# to undo stack even after it will be deleted in check_error which is
# fine since verified_delete succeeds on deleted server
undo.push(verified_delete, log, server_endpoint, new_request_bag,
server_id)
ilog[0] = log.bind(server_id=server_id)
return wait_for_active(ilog[0], server_endpoint,
new_request_bag.auth_token,
server_id).addCallback(check_metadata)
def add_lb(server, new_request_bag):
if lb_config:
lbd = add_to_load_balancers(ilog[0], new_request_bag, lb_config,
server, undo)
lbd.addCallback(lambda lb_response: (server, lb_response))
return lbd
return (server, [])
def _real_create_server(new_request_bag):
auth_token = new_request_bag.auth_token
d = create_server(server_endpoint, auth_token, server_config, log=log)
d.addCallback(wait_for_server, new_request_bag)
d.addCallback(add_lb, new_request_bag)
return d
def _create_server():
return request_bag.re_auth().addCallback(_real_create_server)
def check_error(f):
f.trap(UnexpectedServerStatus)
if f.value.status == 'ERROR':
log.msg(
'{server_id} errored, deleting and creating new '
'server instead',
server_id=f.value.server_id)
# trigger server delete and return True to allow retry
verified_delete(log, server_endpoint, request_bag,
f.value.server_id)
return True
else:
return False
d = retry(_create_server,
can_retry=compose_retries(retry_times(3), check_error),
next_interval=repeating_interval(15),
clock=clock)
return d
def add_to_clb(log,
endpoint,
auth_token,
lb_config,
ip_address,
undo,
clock=None):
"""
Add an IP address to a Cloud Load Balancer based on the ``lb_config``.
TODO: Handle load balancer node metadata.
:param log: A bound logger
:param str endpoint: Load balancer endpoint URI.
:param str auth_token: Keystone auth token.
:param dict lb_config: An ``lb_config`` dictionary.
:param str ip_address: The IP address of the node to add to the load
balancer.
:param IUndoStack undo: An IUndoStack to push any reversable operations
onto.
:return: Deferred that fires with the load balancer response.
"""
lb_id = lb_config['loadBalancerId']
port = lb_config['port']
path = append_segments(endpoint, 'loadbalancers', str(lb_id), 'nodes')
lb_log = log.bind(loadbalancer_id=lb_id, ip_address=ip_address)
def add():
d = treq.post(path,
headers=headers(auth_token),
data=json.dumps({
"nodes": [{
"address": ip_address,
"port": port,
"condition": "ENABLED",
"type": "PRIMARY"
}]
}),
log=lb_log)
d.addCallback(check_success, [200, 202])
d.addErrback(log_lb_unexpected_errors, lb_log, 'add_node')
d.addErrback(wrap_request_error, path, 'add_node')
d.addErrback(check_deleted_clb, lb_id)
return d
d = retry(add,
can_retry=compose_retries(
transient_errors_except(CLBOrNodeDeleted),
retry_times(
config_value('worker.lb_max_retries')
or LB_MAX_RETRIES)),
next_interval=random_interval(
*(config_value('worker.lb_retry_interval_range')
or LB_RETRY_INTERVAL_RANGE)),
clock=clock)
def when_done(result):
node_id = result['nodes'][0]['id']
lb_log.msg('Added to load balancer', node_id=node_id)
undo.push(_remove_from_clb, lb_log, endpoint, auth_token, lb_id,
node_id)
return result
return d.addCallback(treq.json_content).addCallback(when_done)
def create_server(server_endpoint,
auth_token,
server_config,
log=None,
clock=None,
retries=3,
create_failure_delay=5,
_treq=None):
"""
Create a new server. If there is an error from Nova from this call,
checks to see if the server was created anyway. If not, will retry the
create ``retries`` times (checking each time if a server).
If the error from Nova is a 400, does not retry, because that implies that
retrying will just result in another 400 (bad args).
If checking to see if the server is created also results in a failure,
does not retry because there might just be something wrong with Nova.
:param str server_endpoint: Server endpoint URI.
:param str auth_token: Keystone Auth Token.
:param dict server_config: Nova server config.
:param: int retries: Number of tries to retry the create.
:param: int create_failure_delay: how much time in seconds to wait after
a create server failure before checking Nova to see if a server
was created
:param log: logger
:type log: :class:`otter.log.bound.BoundLog`
:param _treq: To be used for testing - what treq object to use
:type treq: something with the same api as :obj:`treq`
:return: Deferred that fires with the CreateServer response as a dict.
"""
path = append_segments(server_endpoint, 'servers')
if _treq is None: # pragma: no cover
_treq = treq
if clock is None: # pragma: no cover
from twisted.internet import reactor
clock = reactor
def _check_results(result, propagated_f):
"""
Return the original failure, if checking a server resulted in a
failure too. Returns a wrapped propagated failure, if there were no
servers created, so that the retry utility knows that server creation
can be retried.
"""
if isinstance(result, Failure):
log.msg(
"Attempt to find a created server in nova resulted in "
"{failure}. Propagating the original create error instead.",
failure=result)
return propagated_f
if result is None:
raise _NoCreatedServerFound(propagated_f)
return result
def _check_server_created(f):
"""
If creating a server failed with anything other than a 400, see if
Nova created a server anyway (a 400 means that the server creation args
were bad, and there is no point in retrying).
If Nova created a server, just return it and pretend that the error
never happened. If it didn't, or if checking resulted in another
failure response, return a failure of some type.
"""
f.trap(APIError)
if f.value.code == 400:
return f
d = deferLater(clock,
create_failure_delay,
find_server,
server_endpoint,
auth_token,
server_config,
log=log)
d.addBoth(_check_results, f)
return d
def _create_with_delay(to_delay):
d = _treq.post(path,
headers=headers(auth_token),
data=json.dumps({'server': server_config}),
log=log)
if to_delay:
# Add 1 second delay to space 1 second between server creations
d.addCallback(delay, clock, 1)
return d
def _create_server():
"""
Attempt to create a server, handling spurious non-400 errors from Nova
by seeing if Nova created a server anyway in spite of the error. If so
then create server succeeded.
If not, and if no further errors occur, server creation can be retried.
"""
sem = get_sempahore("create_server", "worker.create_server_limit")
if sem is not None:
d = sem.run(_create_with_delay, True)
else:
d = _create_with_delay(False)
d.addCallback(check_success, [202], _treq=_treq)
d.addCallback(_treq.json_content)
d.addErrback(_check_server_created)
return d
def _unwrap_NoCreatedServerFound(f):
"""
The original failure was wrapped in a :class:`_NoCreatedServerFound`
for ease of retry, but that should not be the final error propagated up
by :func:`create_server`.
This errback unwraps the :class:`_NoCreatedServerFound` error and
returns the original failure.
"""
f.trap(_NoCreatedServerFound)
return f.value.original
d = retry(_create_server,
can_retry=compose_retries(
retry_times(retries),
terminal_errors_except(_NoCreatedServerFound)),
next_interval=repeating_interval(15),
clock=clock)
d.addErrback(_unwrap_NoCreatedServerFound)
d.addErrback(wrap_request_error, path, 'server_create')
return d
def launch_server(log, request_bag, scaling_group, launch_config, undo,
clock=None):
"""
Launch a new server given the launch config auth tokens and service
catalog. Possibly adding the newly launched server to a load balancer.
:param BoundLog log: A bound logger.
:param request_bag: An object with a bunch of useful data on it, including
a callable to re-auth and get a new token.
:param IScalingGroup scaling_group: The scaling group to add the launched
server to.
:param dict launch_config: A launch_config args structure as defined for
the launch_server_v1 type.
:param IUndoStack undo: The stack that will be rewound if undo fails.
:return: Deferred that fires with a 2-tuple of server details and the
list of load balancer responses from add_to_load_balancers.
"""
launch_config = prepare_launch_config(scaling_group.uuid, launch_config)
cloudServersOpenStack = config_value('cloudServersOpenStack')
server_endpoint = public_endpoint_url(request_bag.service_catalog,
cloudServersOpenStack,
request_bag.region)
lb_config = launch_config.get('loadBalancers', [])
server_config = launch_config['server']
log = log.bind(server_name=server_config['name'])
ilog = [None]
def check_metadata(server):
# sanity check to make sure the metadata didn't change - can probably
# be removed after a while if we do not see any log messages from this
# function
expected = launch_config['server']['metadata']
result = server['server'].get('metadata')
if result != expected:
ilog[0].msg('Server metadata has changed.',
sanity_check=True,
expected_metadata=expected,
nova_metadata=result)
return server
def wait_for_server(server, new_request_bag):
server_id = server['server']['id']
# NOTE: If server create is retried, each server delete will be pushed
# to undo stack even after it will be deleted in check_error which is
# fine since verified_delete succeeds on deleted server
undo.push(
verified_delete, log, server_endpoint, new_request_bag, server_id)
ilog[0] = log.bind(server_id=server_id)
return wait_for_active(
ilog[0],
server_endpoint,
new_request_bag.auth_token,
server_id).addCallback(check_metadata)
def add_lb(server, new_request_bag):
if lb_config:
lbd = add_to_load_balancers(
ilog[0], new_request_bag, lb_config, server, undo)
lbd.addCallback(lambda lb_response: (server, lb_response))
return lbd
return (server, [])
def _real_create_server(new_request_bag):
auth_token = new_request_bag.auth_token
d = create_server(server_endpoint, auth_token, server_config, log=log)
d.addCallback(wait_for_server, new_request_bag)
d.addCallback(add_lb, new_request_bag)
return d
def _create_server():
return request_bag.re_auth().addCallback(_real_create_server)
def check_error(f):
f.trap(UnexpectedServerStatus)
if f.value.status == 'ERROR':
log.msg('{server_id} errored, deleting and creating new '
'server instead', server_id=f.value.server_id)
# trigger server delete and return True to allow retry
verified_delete(log, server_endpoint, request_bag,
f.value.server_id)
return True
else:
return False
d = retry(_create_server,
can_retry=compose_retries(retry_times(3), check_error),
next_interval=repeating_interval(15), clock=clock)
return d
def create_server(server_endpoint, auth_token, server_config, log=None,
clock=None, retries=3, create_failure_delay=5, _treq=None):
"""
Create a new server. If there is an error from Nova from this call,
checks to see if the server was created anyway. If not, will retry the
create ``retries`` times (checking each time if a server).
If the error from Nova is a 400, does not retry, because that implies that
retrying will just result in another 400 (bad args).
If checking to see if the server is created also results in a failure,
does not retry because there might just be something wrong with Nova.
:param str server_endpoint: Server endpoint URI.
:param str auth_token: Keystone Auth Token.
:param dict server_config: Nova server config.
:param: int retries: Number of tries to retry the create.
:param: int create_failure_delay: how much time in seconds to wait after
a create server failure before checking Nova to see if a server
was created
:param log: logger
:type log: :class:`otter.log.bound.BoundLog`
:param _treq: To be used for testing - what treq object to use
:type treq: something with the same api as :obj:`treq`
:return: Deferred that fires with the CreateServer response as a dict.
"""
path = append_segments(server_endpoint, 'servers')
if _treq is None: # pragma: no cover
_treq = treq
if clock is None: # pragma: no cover
from twisted.internet import reactor
clock = reactor
def _check_results(result, propagated_f):
"""
Return the original failure, if checking a server resulted in a
failure too. Returns a wrapped propagated failure, if there were no
servers created, so that the retry utility knows that server creation
can be retried.
"""
if isinstance(result, Failure):
log.msg("Attempt to find a created server in nova resulted in "
"{failure}. Propagating the original create error instead.",
failure=result)
return propagated_f
if result is None:
raise _NoCreatedServerFound(propagated_f)
return result
def _check_server_created(f):
"""
If creating a server failed with anything other than a 400, see if
Nova created a server anyway (a 400 means that the server creation args
were bad, and there is no point in retrying).
If Nova created a server, just return it and pretend that the error
never happened. If it didn't, or if checking resulted in another
failure response, return a failure of some type.
"""
f.trap(APIError)
if f.value.code == 400:
return f
d = deferLater(clock, create_failure_delay, find_server,
server_endpoint, auth_token, server_config, log=log)
d.addBoth(_check_results, f)
return d
def _create_with_delay(to_delay):
d = _treq.post(path, headers=headers(auth_token),
data=json.dumps({'server': server_config}), log=log)
if to_delay:
# Add 1 second delay to space 1 second between server creations
d.addCallback(delay, clock, 1)
return d
def _create_server():
"""
Attempt to create a server, handling spurious non-400 errors from Nova
by seeing if Nova created a server anyway in spite of the error. If so
then create server succeeded.
If not, and if no further errors occur, server creation can be retried.
"""
sem = get_sempahore("create_server", "worker.create_server_limit")
if sem is not None:
d = sem.run(_create_with_delay, True)
else:
d = _create_with_delay(False)
d.addCallback(check_success, [202], _treq=_treq)
d.addCallback(_treq.json_content)
d.addErrback(_check_server_created)
return d
def _unwrap_NoCreatedServerFound(f):
"""
The original failure was wrapped in a :class:`_NoCreatedServerFound`
for ease of retry, but that should not be the final error propagated up
by :func:`create_server`.
This errback unwraps the :class:`_NoCreatedServerFound` error and
returns the original failure.
"""
f.trap(_NoCreatedServerFound)
return f.value.original
d = retry(
_create_server,
can_retry=compose_retries(
retry_times(retries),
terminal_errors_except(_NoCreatedServerFound)),
next_interval=repeating_interval(15), clock=clock)
d.addErrback(_unwrap_NoCreatedServerFound)
d.addErrback(wrap_request_error, path, 'server_create')
return d
def launch_server(log, region, scaling_group, service_catalog, auth_token,
launch_config, undo, clock=None):
"""
Launch a new server given the launch config auth tokens and service catalog.
Possibly adding the newly launched server to a load balancer.
:param BoundLog log: A bound logger.
:param str region: A rackspace region as found in the service catalog.
:param IScalingGroup scaling_group: The scaling group to add the launched
server to.
:param list service_catalog: A list of services as returned by the auth apis.
:param str auth_token: The user's auth token.
:param dict launch_config: A launch_config args structure as defined for
the launch_server_v1 type.
:param IUndoStack undo: The stack that will be rewound if undo fails.
:return: Deferred that fires with a 2-tuple of server details and the
list of load balancer responses from add_to_load_balancers.
"""
launch_config = prepare_launch_config(scaling_group.uuid, launch_config)
lb_region = config_value('regionOverrides.cloudLoadBalancers') or region
cloudLoadBalancers = config_value('cloudLoadBalancers')
cloudServersOpenStack = config_value('cloudServersOpenStack')
lb_endpoint = public_endpoint_url(service_catalog,
cloudLoadBalancers,
lb_region)
server_endpoint = public_endpoint_url(service_catalog,
cloudServersOpenStack,
region)
lb_config = launch_config.get('loadBalancers', [])
server_config = launch_config['server']
log = log.bind(server_name=server_config['name'])
ilog = [None]
def wait_for_server(server):
server_id = server['server']['id']
# NOTE: If server create is retried, each server delete will be pushed
# to undo stack even after it will be deleted in check_error which is fine
# since verified_delete succeeds on deleted server
undo.push(
verified_delete, log, server_endpoint, auth_token, server_id)
ilog[0] = log.bind(server_id=server_id)
return wait_for_active(
ilog[0],
server_endpoint,
auth_token,
server_id)
def add_lb(server):
ip_address = private_ip_addresses(server)[0]
lbd = add_to_load_balancers(
ilog[0], lb_endpoint, auth_token, lb_config, ip_address, undo)
lbd.addCallback(lambda lb_response: (server, lb_response))
return lbd
def _create_server():
d = create_server(server_endpoint, auth_token, server_config, log=log)
d.addCallback(wait_for_server)
d.addCallback(add_lb)
return d
def check_error(f):
f.trap(UnexpectedServerStatus)
if f.value.status == 'ERROR':
log.msg('{server_id} errored, deleting and creating new server instead',
server_id=f.value.server_id)
# trigger server delete and return True to allow retry
verified_delete(log, server_endpoint, auth_token, f.value.server_id)
return True
else:
return False
d = retry(_create_server, can_retry=compose_retries(retry_times(3), check_error),
next_interval=repeating_interval(15), clock=clock)
return d
