openstack運維實戰系列(七)之cinder配額調整

1. 前言

    openstack默認爲了防止用戶隨意使用存儲空間，默認針對cinder作了限制，防止用戶過分使用存儲空間，和nova與neutron相相似，cinder的quota也是有一個專門的驅動來完成，當超過quota時，使用cinder將會失敗。

2. cinder默認的quota

1. 默認配置

quota_driver=cinder.quota.DbQuotaDriver            quota的驅動，源代碼的路徑
quota_volumes=10                                   volume的個數
quota_snapshots=10                                 快照個數
quota_gigabytes=1000                               volume的空間大小，默認單位是GB，包括快照和volume的空間
reservation_expire=86400                           過時時長
max_age=0                                          刷新間隔

2. 查看tenant默認的配額

[root@controller ~]# cinder quota-defaults  7ff1dfb5a6f349958c3a949248e56236           
+-----------+-------+
|  Property | Value |
+-----------+-------+
| gigabytes |  1000 |                            容許使用的空間
| snapshots |  10   |                            快照的個數
|  volumes  |  10   |                            volume的個數

3. 查看quota的使用狀況

[root@controller ~]# cinder quota-usage 7ff1dfb5a6f349958c3a949248e56236   
+-----------+--------+----------+-------+
|    Type   | In_use | Reserved | Limit |
+-----------+--------+----------+-------+
| gigabytes |   0    |    0     | 1000  |
| snapshots |   0    |    0     |  10   |
|  volumes  |   0    |    0     |  10   |
+-----------+--------+----------+-------+

3. 調整quota配置

[root@controller ~]# cinder quota-update --volumes 100 --snapshots 100 --gigabytes 5000 7ff1dfb5a6f349958c3a949248e56236
[root@controller ~]# cinder quota-show 7ff1dfb5a6f349958c3a949248e56236
+-----------+-------+
|  Property | Value |
+-----------+-------+
| gigabytes |  5000 |
| snapshots |  100  |
|  volumes  |  100  |
+-----------+-------+
[root@controller ~]# cinder quota-usage 7ff1dfb5a6f349958c3a949248e56236
+-----------+--------+----------+-------+
|    Type   | In_use | Reserved | Limit |
+-----------+--------+----------+-------+
| gigabytes |   0    |    0     |  5000 |
| snapshots |   0    |    0     |  100  |
|  volumes  |   0    |    0     |  100  |
+-----------+--------+----------+-------+

4. 總結

    關於cinder quota的配置，只須要藉助cinder quota*相關的子命令便可完成配額的調整，在實際的生產環境中，隨着volume的個數和存儲空間的增大，當達到cinder的quota以後，將沒法創建cinder的volume，具體的信息能夠參考/var/log/cinder/cinder.api.log中查看便可，能夠根據日誌的提示內容，修改quota便可。

5. 附錄

    關於cinder quota的源代碼，能夠參考以下內容

"""Quotas for volumes."""
import datetime
from oslo.config import cfg
from cinder import context
from cinder import db
from cinder import exception
from cinder.openstack.common import importutils
from cinder.openstack.common import log as logging
from cinder.openstack.common import timeutils
LOG = logging.getLogger(__name__)
'''
在cinder的配置文件中，註冊quota的配置選項，包括volume,snpshots,gigabytes空間，driver等
'''
quota_opts = [
    cfg.IntOpt('quota_volumes',
               default=10,
               help='number of volumes allowed per project'),
    cfg.IntOpt('quota_snapshots',
               default=10,
               help='number of volume snapshots allowed per project'),
    cfg.IntOpt('quota_gigabytes',
               default=1000,
               help='number of volume gigabytes (snapshots are also included) '
                    'allowed per project'),
    cfg.IntOpt('reservation_expire',
               default=86400,
               help='number of seconds until a reservation expires'),
    cfg.IntOpt('until_refresh',
               default=0,
               help='count of reservations until usage is refreshed'),
    cfg.IntOpt('max_age',
               default=0,
               help='number of seconds between subsequent usage refreshes'),
    cfg.StrOpt('quota_driver',
               default='cinder.quota.DbQuotaDriver',
               help='default driver to use for quota checks'),
    cfg.BoolOpt('use_default_quota_class',
                default=True,
                help='whether to use default quota class for default quota'), ]
CONF = cfg.CONF
CONF.register_opts(quota_opts)
'''
cinder quota的管理驅動，即包含了增刪改查，和cinder配額的校驗函數，都封裝在該class內，cinder的quota和nova的quota實現方式很是相似
'''
class DbQuotaDriver(object):
    """Driver to perform check to enforcement of quotas.
    Also allows to obtain quota information.
    The default driver utilizes the local database.
    """
    
    #獲取tenant的quota信息，即cinder quota-show <tenant_id>的實現函數
    def get_by_project(self, context, project_id, resource_name):
        """Get a specific quota by project."""
        #從數據庫中，調用nova.db.api下的quota_get()函數，返回數據庫中關於tenant的配置信息
        return db.quota_get(context, project_id, resource_name)     
    def get_by_class(self, context, quota_class, resource_name):
        """Get a specific quota by quota class."""
        return db.quota_class_get(context, quota_class, resource_name)
    #獲取默認的quota配置信息，經過調用quota_class_get_default()方法實現
    def get_default(self, context, resource):
        """Get a specific default quota for a resource."""
        default_quotas = db.quota_class_get_default(context)
        return default_quotas.get(resource.name, resource.default)
    #調用系統默認的cinder quota配置內容
    def get_defaults(self, context, resources):
        """Given a list of resources, retrieve the default quotas.
        Use the class quotas named `_DEFAULT_QUOTA_NAME` as default quotas,
        if it exists.
        :param context: The request context, for access checks.
        :param resources: A dictionary of the registered resources.
        """
        quotas = {}
        default_quotas = {}
        if CONF.use_default_quota_class:
            default_quotas = db.quota_class_get_default(context)
        for resource in resources.values():
            if resource.name not in default_quotas:
                LOG.deprecated(_("Default quota for resource: %(res)s is set "
                                 "by the default quota flag: quota_%(res)s, "
                                 "it is now deprecated. Please use the "
                                 "the default quota class for default "
                                 "quota.") % {'res': resource.name})
            quotas[resource.name] = default_quotas.get(resource.name,
                                                       resource.default)
        return quotas
    def get_class_quotas(self, context, resources, quota_class,
                         defaults=True):
        """Given list of resources, retrieve the quotas for given quota class.
        :param context: The request context, for access checks.
        :param resources: A dictionary of the registered resources.
        :param quota_class: The name of the quota class to return
                            quotas for.
        :param defaults: If True, the default value will be reported
                         if there is no specific value for the
                         resource.
        """
        quotas = {}
        default_quotas = {}
        class_quotas = db.quota_class_get_all_by_name(context, quota_class)
        if defaults:
            default_quotas = db.quota_class_get_default(context)
        for resource in resources.values():
            if resource.name in class_quotas:
                quotas[resource.name] = class_quotas[resource.name]
                continue
            if defaults:
                quotas[resource.name] = default_quotas.get(resource.name,
                                                           resource.default)
        return quotas
    '''
            獲取tenant的配額信息
    '''
    def get_project_quotas(self, context, resources, project_id,
                           quota_class=None, defaults=True,
                           usages=True):
        """Given a list of resources, retrieve the quotas for the given
        project.
        :param context: The request context, for access checks.
        :param resources: A dictionary of the registered resources.
        :param project_id: The ID of the project to return quotas for.
        :param quota_class: If project_id != context.project_id, the
                            quota class cannot be determined.  This
                            parameter allows it to be specified.  It
                            will be ignored if project_id ==
                            context.project_id.
        :param defaults: If True, the quota class value (or the
                         default value, if there is no value from the
                         quota class) will be reported if there is no
                         specific value for the resource.
        :param usages: If True, the current in_use and reserved counts
                       will also be returned.
        """
        quotas = {}
        project_quotas = db.quota_get_all_by_project(context, project_id)
        if usages:
            project_usages = db.quota_usage_get_all_by_project(context,
                                                               project_id)
        # Get the quotas for the appropriate class.  If the project ID
        # matches the one in the context, we use the quota_class from
        # the context, otherwise, we use the provided quota_class (if
        # any)
        if project_id == context.project_id:
            quota_class = context.quota_class
        if quota_class:
            class_quotas = db.quota_class_get_all_by_name(context, quota_class)
        else:
            class_quotas = {}
        default_quotas = self.get_defaults(context, resources)
        for resource in resources.values():
            # Omit default/quota class values
            if not defaults and resource.name not in project_quotas:
                continue
            quotas[resource.name] = dict(
                limit=project_quotas.get(
                    resource.name,
                    class_quotas.get(resource.name,
                                     default_quotas[resource.name])),
            )
            # Include usages if desired.  This is optional because one
            # internal consumer of this interface wants to access the
            # usages directly from inside a transaction.
            if usages:
                usage = project_usages.get(resource.name, {})
                quotas[resource.name].update(
                    in_use=usage.get('in_use', 0),
                    reserved=usage.get('reserved', 0), )
        return quotas
    def _get_quotas(self, context, resources, keys, has_sync, project_id=None):
        """A helper method which retrieves the quotas for specific resources.
        This specific resource is identified by keys, and which apply to the
        current context.
        :param context: The request context, for access checks.
        :param resources: A dictionary of the registered resources.
        :param keys: A list of the desired quotas to retrieve.
        :param has_sync: If True, indicates that the resource must
                         have a sync attribute; if False, indicates
                         that the resource must NOT have a sync
                         attribute.
        :param project_id: Specify the project_id if current context
                           is admin and admin wants to impact on
                           common user's tenant.
        """
        # Filter resources
        if has_sync:
            sync_filt = lambda x: hasattr(x, 'sync')
        else:
            sync_filt = lambda x: not hasattr(x, 'sync')
        desired = set(keys)
        sub_resources = dict((k, v) for k, v in resources.items()
                             if k in desired and sync_filt(v))
        # Make sure we accounted for all of them...
        if len(keys) != len(sub_resources):
            unknown = desired - set(sub_resources.keys())
            raise exception.QuotaResourceUnknown(unknown=sorted(unknown))
        # Grab and return the quotas (without usages)
        quotas = self.get_project_quotas(context, sub_resources,
                                         project_id,
                                         context.quota_class, usages=False)
        return dict((k, v['limit']) for k, v in quotas.items())
    '''
                配額的檢查函數
    '''
    def limit_check(self, context, resources, values, project_id=None):
        """Check simple quota limits.
        For limits--those quotas for which there is no usage
        synchronization function--this method checks that a set of
        proposed values are permitted by the limit restriction.
        This method will raise a QuotaResourceUnknown exception if a
        given resource is unknown or if it is not a simple limit
        resource.
        If any of the proposed values is over the defined quota, an
        OverQuota exception will be raised with the sorted list of the
        resources which are too high.  Otherwise, the method returns
        nothing.
        :param context: The request context, for access checks.
        :param resources: A dictionary of the registered resources.
        :param values: A dictionary of the values to check against the
                       quota.
        :param project_id: Specify the project_id if current context
                           is admin and admin wants to impact on
                           common user's tenant.
        """
        # Ensure no value is less than zero
        unders = [key for key, val in values.items() if val < 0]
        if unders:
            raise exception.InvalidQuotaValue(unders=sorted(unders))
        # If project_id is None, then we use the project_id in context
        if project_id is None:
            project_id = context.project_id
        # Get the applicable quotas
        quotas = self._get_quotas(context, resources, values.keys(),
                                  has_sync=False, project_id=project_id)
        # Check the quotas and construct a list of the resources that
        # would be put over limit by the desired values
        overs = [key for key, val in values.items()
                 if quotas[key] >= 0 and quotas[key] < val]
        if overs:
            raise exception.OverQuota(overs=sorted(overs), quotas=quotas,
                                      usages={})
    def reserve(self, context, resources, deltas, expire=None,
                project_id=None):
        """Check quotas and reserve resources.
        For counting quotas--those quotas for which there is a usage
        synchronization function--this method checks quotas against
        current usage and the desired deltas.
        This method will raise a QuotaResourceUnknown exception if a
        given resource is unknown or if it does not have a usage
        synchronization function.
        If any of the proposed values is over the defined quota, an
        OverQuota exception will be raised with the sorted list of the
        resources which are too high.  Otherwise, the method returns a
        list of reservation UUIDs which were created.
        :param context: The request context, for access checks.
        :param resources: A dictionary of the registered resources.
        :param deltas: A dictionary of the proposed delta changes.
        :param expire: An optional parameter specifying an expiration
                       time for the reservations.  If it is a simple
                       number, it is interpreted as a number of
                       seconds and added to the current time; if it is
                       a datetime.timedelta object, it will also be
                       added to the current time.  A datetime.datetime
                       object will be interpreted as the absolute
                       expiration time.  If None is specified, the
                       default expiration time set by
                       --default-reservation-expire will be used (this
                       value will be treated as a number of seconds).
        :param project_id: Specify the project_id if current context
                           is admin and admin wants to impact on
                           common user's tenant.
        """
        # Set up the reservation expiration
        if expire is None:
            expire = CONF.reservation_expire
        if isinstance(expire, (int, long)):
            expire = datetime.timedelta(seconds=expire)
        if isinstance(expire, datetime.timedelta):
            expire = timeutils.utcnow() + expire
        if not isinstance(expire, datetime.datetime):
            raise exception.InvalidReservationExpiration(expire=expire)
        # If project_id is None, then we use the project_id in context
        if project_id is None:
            project_id = context.project_id
        # Get the applicable quotas.
        # NOTE(Vek): We're not worried about races at this point.
        #            Yes, the admin may be in the process of reducing
        #            quotas, but that's a pretty rare thing.
        quotas = self._get_quotas(context, resources, deltas.keys(),
                                  has_sync=True, project_id=project_id)
        # NOTE(Vek): Most of the work here has to be done in the DB
        #            API, because we have to do it in a transaction,
        #            which means access to the session.  Since the
        #            session isn't available outside the DBAPI, we
        #            have to do the work there.
        return db.quota_reserve(context, resources, quotas, deltas, expire,
                                CONF.until_refresh, CONF.max_age,
                                project_id=project_id)
    '''
                提交確認函數
    '''
    def commit(self, context, reservations, project_id=None):
        """Commit reservations.
        :param context: The request context, for access checks.
        :param reservations: A list of the reservation UUIDs, as
                             returned by the reserve() method.
        :param project_id: Specify the project_id if current context
                           is admin and admin wants to impact on
                           common user's tenant.
        """
        # If project_id is None, then we use the project_id in context
        if project_id is None:
            project_id = context.project_id
        db.reservation_commit(context, reservations, project_id=project_id)
    #回滾函數
    def rollback(self, context, reservations, project_id=None):
        """Roll back reservations.
        :param context: The request context, for access checks.
        :param reservations: A list of the reservation UUIDs, as
                             returned by the reserve() method.
        :param project_id: Specify the project_id if current context
                           is admin and admin wants to impact on
                           common user's tenant.
        """
        # If project_id is None, then we use the project_id in context
        if project_id is None:
            project_id = context.project_id
        db.reservation_rollback(context, reservations, project_id=project_id)
    #刪除tenant的配額，即執行cinder quota-delete的操做，恢復到默認值
    def destroy_all_by_project(self, context, project_id):
        """Destroy all that is associated with a project.
        This includes quotas, usages and reservations.
        :param context: The request context, for access checks.
        :param project_id: The ID of the project being deleted.
        """
        db.quota_destroy_all_by_project(context, project_id)
    #保留過時的cinder
    def expire(self, context):
        """Expire reservations.
        Explores all currently existing reservations and rolls back
        any that have expired.
        :param context: The request context, for access checks.
        """
        db.reservation_expire(context)