deb-manila/manila/share/migration.py

219 lines
8.5 KiB
Python

# Copyright (c) 2015 Hitachi Data Systems.
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
"""Helper class for Share Migration."""
import time
from oslo_config import cfg
from oslo_log import log
from manila.common import constants
from manila import exception
from manila.i18n import _, _LW
from manila.share import api as share_api
import manila.utils as utils
LOG = log.getLogger(__name__)
migration_opts = [
cfg.IntOpt(
'migration_wait_access_rules_timeout',
default=180,
help="Time to wait for access rules to be allowed/denied on backends "
"when migrating shares using generic approach (seconds)."),
cfg.IntOpt(
'migration_create_delete_share_timeout',
default=300,
help='Timeout for creating and deleting share instances '
'when performing share migration (seconds).'),
]
CONF = cfg.CONF
CONF.register_opts(migration_opts)
class ShareMigrationHelper(object):
def __init__(self, context, db, share):
self.db = db
self.share = share
self.context = context
self.api = share_api.API()
self.migration_create_delete_share_timeout = (
CONF.migration_create_delete_share_timeout)
self.migration_wait_access_rules_timeout = (
CONF.migration_wait_access_rules_timeout)
def delete_instance_and_wait(self, share_instance):
self.api.delete_instance(self.context, share_instance, True)
# Wait for deletion.
starttime = time.time()
deadline = starttime + self.migration_create_delete_share_timeout
tries = 0
instance = "Something not None"
while instance is not None:
try:
instance = self.db.share_instance_get(self.context,
share_instance['id'])
tries += 1
now = time.time()
if now > deadline:
msg = _("Timeout trying to delete instance "
"%s") % share_instance['id']
raise exception.ShareMigrationFailed(reason=msg)
except exception.NotFound:
instance = None
else:
time.sleep(tries ** 2)
def create_instance_and_wait(self, share, dest_host, new_share_network_id,
new_az_id, new_share_type_id):
new_share_instance = self.api.create_instance(
self.context, share, new_share_network_id, dest_host,
new_az_id, share_type_id=new_share_type_id)
# Wait for new_share_instance to become ready
starttime = time.time()
deadline = starttime + self.migration_create_delete_share_timeout
new_share_instance = self.db.share_instance_get(
self.context, new_share_instance['id'], with_share_data=True)
tries = 0
while new_share_instance['status'] != constants.STATUS_AVAILABLE:
tries += 1
now = time.time()
if new_share_instance['status'] == constants.STATUS_ERROR:
msg = _("Failed to create new share instance"
" (from %(share_id)s) on "
"destination host %(host_name)s") % {
'share_id': share['id'], 'host_name': dest_host}
self.cleanup_new_instance(new_share_instance)
raise exception.ShareMigrationFailed(reason=msg)
elif now > deadline:
msg = _("Timeout creating new share instance "
"(from %(share_id)s) on "
"destination host %(host_name)s") % {
'share_id': share['id'], 'host_name': dest_host}
self.cleanup_new_instance(new_share_instance)
raise exception.ShareMigrationFailed(reason=msg)
else:
time.sleep(tries ** 2)
new_share_instance = self.db.share_instance_get(
self.context, new_share_instance['id'], with_share_data=True)
return new_share_instance
# NOTE(ganso): Cleanup methods do not throw exceptions, since the
# exceptions that should be thrown are the ones that call the cleanup
def cleanup_new_instance(self, new_instance):
try:
self.delete_instance_and_wait(new_instance)
except Exception:
LOG.warning(_LW("Failed to cleanup new instance during generic"
" migration for share %s."), self.share['id'])
def cleanup_access_rules(self, share_instance, share_server, driver):
try:
self.revert_access_rules(share_instance, share_server, driver)
except Exception:
LOG.warning(_LW("Failed to cleanup access rules during generic"
" migration for share %s."), self.share['id'])
def change_to_read_only(self, share_instance, share_server,
readonly_support, driver):
# NOTE(ganso): If the share does not allow readonly mode we
# should remove all access rules and prevent any access
rules = self.db.share_access_get_all_for_instance(
self.context, share_instance['id'])
if len(rules) > 0:
if readonly_support:
LOG.debug("Changing all of share %s access rules "
"to read-only.", self.share['id'])
for rule in rules:
rule['access_level'] = constants.ACCESS_LEVEL_RO
driver.update_access(self.context, share_instance, rules,
add_rules=[], delete_rules=[],
share_server=share_server)
else:
LOG.debug("Removing all access rules for migration of "
"share %s." % self.share['id'])
driver.update_access(self.context, share_instance, [],
add_rules=[], delete_rules=rules,
share_server=share_server)
def revert_access_rules(self, share_instance, share_server, driver):
rules = self.db.share_access_get_all_for_instance(
self.context, share_instance['id'])
if len(rules) > 0:
LOG.debug("Restoring all of share %s access rules according to "
"DB.", self.share['id'])
driver.update_access(self.context, share_instance, rules,
add_rules=[], delete_rules=[],
share_server=share_server)
def apply_new_access_rules(self, new_share_instance):
self.db.share_instance_access_copy(self.context, self.share['id'],
new_share_instance['id'])
rules = self.db.share_access_get_all_for_instance(
self.context, new_share_instance['id'])
if len(rules) > 0:
LOG.debug("Restoring all of share %s access rules according to "
"DB.", self.share['id'])
# refresh share instance
new_share_instance = self.db.share_instance_get(
self.context, new_share_instance['id'], with_share_data=True)
self.api.allow_access_to_instance(self.context, new_share_instance,
rules)
utils.wait_for_access_update(
self.context, self.db, new_share_instance,
self.migration_wait_access_rules_timeout)
@utils.retry(exception.ShareServerNotReady, retries=8)
def wait_for_share_server(self, share_server_id):
share_server = self.db.share_server_get(self.context, share_server_id)
if share_server['status'] == constants.STATUS_ERROR:
raise exception.ShareServerNotCreated(
share_server_id=share_server_id)
elif share_server['status'] == constants.STATUS_ACTIVE:
return share_server
else:
raise exception.ShareServerNotReady(
share_server_id=share_server_id, time=511,
state=constants.STATUS_AVAILABLE)