【单选题】
An administrator attempts to manually reclaim space on thin-provisioned VMFS6 volumes but finds that no additional space is being recovered. Which could be causing this?___
A. vSphere 6.5 does not support manual UNMAP.
B. The manual UNMAP operation has been moved to the vSphere web client.
C. The VASA version is use is incompatible.
D. UNMAP is automated for VMFS6.
查看试卷,进入试卷练习
微信扫一扫,开始刷题
答案
D
解析
暂无解析
相关试题
【单选题】
An administrator has upgraded to vSphere 6.5 and also wants to use Kerberos authentication for NFS. Which can be done to the existing NFSv3 volumes to enable this feature?___
A. Perform a storage rescan on VMFS volumes.
B. Unmount the NFSv3 datastore, and then mount as NFSv4.1 datastore.
C. Nothing. All NFSv3 mounted datastores are upgraded automatically during vSphere upgrades.
D. Perform a scan of new storage devices.
【单选题】
An administrator wants to restore the vCenter Server Appliance 6.5 from backup. Where can this be accomplished?___
A. from the ESXi Host Client
B. from the VMware vSphere Appliance Management Interface
C. from within the VMware vSphere Web Client
D. from the vCenter Server Appliance Installer
【单选题】
The administrator wants to power on VM-K2, which has a 2GHz CPU reservation. VM-M1, VM-M2, and VM-K1 are all powered on. VM-K2 is not powered on. The exhibit shows the parent and child resource reservations. If Resource Pool RP-KID is configured with an expandable reservation, which statement is true?___
A. VM-K2 will be unable to power on because there are insufficient resources.
B. VM-K2 will be able to power on since resource pool RP-KID has 2GHz available.
C. VM-K2 will be unable to power on because only 2GHz are reserved for RP-KID.
D. VM-K2 will receive resource priority and will be able to power on this scenario.
【单选题】
Which is the block size on the VMFS6 datastore?___
A. All small and large file blocks are 8MB.
B. All small and large file blocks are 1MB.
C. Small file blocks are 512KB. large file blocks are 64MB.
D. Small file blocks are 1MB, large file blocks are 512MB.
【单选题】
When installing vCenter Converter Standalone, why must an administrator perform a client-server installation instead of a local installation?___
A. to manage conversion tasks remotely
B. to convert virtual machines as well as physical machines
C. to allow installation of the Converter agent on remote source machines
D. to hot clone physical or virtual machines
【单选题】
Which is required by vCenter Converter Standalone to convert a physical Red Hat Enterprise Linux 7 machine to a virtual machine?___
A. The Linux machine must be powered off.
B. The Linux machine must have the SSH daemon started.
C. The Linux machine must use a static IP address.
D. The Linux machine must have a fully-qualified domain name.
【单选题】
An administrator is troubleshooting network communications between a vCenter Server and an ESXi 6.5 host. Which log shows the related events between these components?___
A. /var/log/fdm.log
B. /var/log/vpxa.log
C. /var/log/hostd.log
D. /var/log/auth.log
【单选题】
An administrator has recently upgraded from vSphere 6.0 to 6.5, and can no longer see the software iSCSI named vmhba33. Which could be the reason for this?___
A. The upgrade has changed the vmhba name.
B. vSphere 6.5 automates iSCSI configurations.
C. vSphere 6.5 no longer supports software iSCSI.
D. The upgrade has deleted the vmhba.
【单选题】
An administrator is trying to vMotion a VM from his datacenter to a recovery site. Which is the maximum allowed RTT (Round-Trip Time) latency between source and destination host?___
A. 100 milliseconds
B. 150 milliseconds
C. 15 milliseconds
D. 10 milliseconds
【单选题】
Which is required for configuring iSCSI Software Adapter network port binding?___
A. VMkernel of the iSCSI traffic must be load balanced using Route based on IP Hash algorithm.
B. VMkernel of the iSCSI traffic must be load balanced using Route based on Source Virtual Port ID algorithm.
C. VMkernel of the iSCSI traffic must be load balanced using Route based on Source MAC Hash algorithm.
D. VMkernel of the iSCSI traffic must be bound to only one active network adapter.
【单选题】
In vSphere Data Protection 6.1, which is the function of a Backup Verification job?___
A. None. Backup Verification job is not a feature of vSphere Data Protection
B. It is a manual task -Power it on -Verify the guest OS -Check started applications
C. It is an automatic process -Restore a virtual machine -Power it on -Verify that the guest OS is booted by communicating with the Backup Verification agent
D. It is an automatic process -Restore a virtual machine -Power it on -Verify that the guest OC is booted by detecting the VMware ToolsTM "heartbeats"
【单选题】
An administrator has enabled vSphere Distributed Switch Health Check. The hosts connected to that Distributed Switch all display an alert:< vSphere Distributed Switch MTU supported status > .The administrator has all of the VMkernel ports MTU sizes set to 1600. Which action will remedy this problem?___
A. Configure the Distributed Switch to MTU 9100.
B. Disconnect and reconnect the physical network cable.
C. Configure the physical switch to MTU 1600.
D. Disable the Distributed Switch MTU.
【单选题】
Which Host Profile Subprofile configuration is used to configure firewall settings for ESXi hosts?___
A. Advanced Configuration Settings
B. General System Settings
C. Security
D. Networking
【单选题】
Where would a vSphere administrator find general vCenter Server logs on a vCenter Server Appliance?___
A. /var/log/vmware/vpxd/
B. /var/log/messages
C. /etc/vmware-vpx/
D. /var/log/vmware/vsan-health/
【单选题】
An administrator wishes to enable network port mirroring based on source port. Which feature should be enabled?___
A. vSphere standard switch port
B. ERSPAN
C. NSX Virtual Wire
D. VLAN
【单选题】
Which CLI command shows the physical uplink status for a vmnic?___
A. esxcli network ip connection list
B. esxcli network ip neighbor list
C. esxcli network nic get
D. esxcli network nic list
【单选题】
Which is the maximum number of block devices (LUNs) that are supported by ESXi hosts that are running version 6.5?___
A. 1024
B. 512
C. 2048
D. 256
【单选题】
When performing a vCenter Server 5.5 for Windows with Microsoft SQL Server Express database migration to vCenter Server Appliance 6.5, which will be the target database?___
A. Microsoft SQL Server Express 2012R2
B. Microsoft SQL Server Standard 2012R2
C. PostgreSQL
D. Oracle DB 11g
【单选题】
An administrator has multiple vCenter Server 6.5 systems but cannot enable Storage I/O Control (SIOC) on a datastore shared by ESXi hosts managed by the vCenter Server systems. Which action should the administrator take to resolve the issue?___
A. Unmount the datastore and then enable SIOC on the vCenter Server system.
B. Configure the datastore to be managed by a single vCenter Server system.
C. Configure Storage DRS and then enable SIOC on the vCenter Server system.
D. Enable Raw Device Mapping (RDM) on the
E. SXi hosts.
【单选题】
“OneAppServer” is a VM template stored in a content library named “LibraryOne”, but the vSphere administrator is not able to use this template for deployment. Why is the administrator unable to deploy OneAppServer?___
A. OneAppServer must be updated before it can be deployed.
B. LibraryOne is a subscribed library and OneAppServer is not downloaded yet.
C. LibraryOne is published and optimized for syncing over HTTP.
D. OneAppServer was imported from a local file on the system.
【单选题】
An administrator sets the Failover Capacity for both CPU and Memory at 25%. Based on the Exhibit below, how much of the cluster’s total CPU resources are still available to power on additional virtual machines?___
A. 45%
B. 25%
C. 70%
D. 60%
【单选题】
Which statement applies to the vSphere Replication appliance?___
A. Only one vSphere Replication appliance can be deployed per vCenter Server instance.
B. VMware Tools in the vSphere Replication appliance can be upgraded.
C. A single vSphere Replication appliance can manage a maximum of 4000 replications.
D. vSphere Replication is available only with the vSphere
E. ssentials Plus license.
【单选题】
Which esxcli namespace can a vSphere Administrator use to adjust the queue depth?___
A. esxcli system module parameters
B. esxcli storage core device
C. esxcli system module set
D. esxcli storage core adapter
【单选题】
Which statement regarding datastore clusters meets VMware’s recommended best practices?___
A. Clusters should contain only datastores presented from the same storage array.
B. Clusters should contain only datastores with equal hardware acceleration capability.
C. Clusters should contain only datastores with the same capacity.
D. Clusters should contain only datastores using the same connection method (iSCSI, FC, etc.).
【单选题】
What VM Monitoring setting would ensure that the maximum reset window for a virtual machine is 24 hours?___
A. Medium
B. Low
C. High
D. Normal
【单选题】
What is the default space threshold for vSphere Storage DRS?___
A. 80%
B. 70%
C. 90%
D. 95%
【单选题】
Which is the correct sequence to upgrade a vSphere infrastructure?___
A. vCenter Server>ESXi host> VMware Tools>VM compatibility
B. ESXi host>vCenter Server> VMware Tools>VM compatibility
C. vCenter host> ESXi host> VM compatibility> VMware Tools
D. ESXi host>vCenter Server> VM compatibility>VMware Tools
【单选题】
An administrator has a large boot from SAN cluster and wants to ensure consistent configuration by using host profiles. What special considerations are required for boot from SAN hosts?___
A. Change the “Device is shared clusterwide” setting to “false” in the host profile.
B. Verify that the boot LUN is correctly identified as the boot device in the host profile.
C. The boot from SAN device must report as a local device.
D. Host profiles are incompatible with boot from SAN hosts.
【单选题】
When using VMware Converter to import a Windows server and improve the consistency of the destination virtual machine, which optional step can be performed immediately prior to powering down the source server?___
A. Perform a final synchronization task.
B. Remove the server from the network.
C. Uninstall production applications.
D. Remove the server from the Active Directory domain.
【单选题】
Restoration of the vCenter Server Appliance is accomplished using which interface?___
A. vSphere Web Client
B. vSphere Client
C. vCenter Server Appliance Management Interface
D. vCenter Server Appliance GUI Installer
【单选题】
When attempting to migrate a virtual machine to another host in the same cluster, the error message, “Select a valid compute resource” returns. What could cause this error?___
A. Both hosts run different versions of ESXi.
B. Both hosts are not sharing the same datastore.
C. VMware Tools is not installed.
D. Virtual machine has an ISO attached.
【单选题】
When will vSphere Data Protection delete the expired backup image of a Platform Service Controller?___
A. Immediately after the retention period has expired.
B. After the expired backup image is restored.
C. During the next backup window following expiry.
D. During the next maintenance window following expiry.
【单选题】
Group A has permission to download files in Content Library. Group B does not have permission to download files in Content Library. If a user is a member of both groups, what will be the result?___
A. The user cannot download file from Content Library.
B. The user can download file from Content Library.
C. The user cannot access Content Library.
D. The user can access Content Library.
【单选题】
An administrator is trying to set up Host Partial Failure Response, but the Automated option is grayed out. What can the administrator change to enable the Automated option?___
A. Change the vSphere DRS Automation level to Partially Automated.
B. Change the vSphere DRS Automation level to Fully Automated.
C. Enable vSphere HA Host Monitoring.
D. Change the vSphere DPM Automation level to Automatic.
【单选题】
When you attempt to open a virtual machine console from the vSphere Web Client, the console does not connect. The following error message appears:<HTTP ERROR 404> <Problem accessin/.Reason: Not Found>. Why did not connect?___
A. Port 443 is in use.
B. Port 9443 is in use.
C. Port 8443 is in use.
D. Port 22443 is in use.
【单选题】
What new feature was introduced to the Content Library in vSphere 6.5?___
A. Mount an ISO directly from the Content Library.
B. Deploy a virtual machine from an OVF Package in a Content Library.
C. Upload a File from a URL to a Library Item.
D. Upload a File from a Local System to a Library Item.
【单选题】
How can an administrator exclude Encryption rights from a support engineer?___
A. Clone the role Virtual machine power user, remove Cryptographic operations privileges.
B. Clone the role Administrator and assign to the support engineer.
C. Clone the role Virtual machine power user and assign to the support engineer.
D. Clone the role No cryptography administrator and select privileges only for the support engineer.
【单选题】
The administrator must back up a vCenter HA deployment. Which component must be backed up?___
A. Passive node
B. Witness node
C. External database
D. Active node
【单选题】
What is the supported protocol to perform remote L3 traffic monitoring in vSphere 6.5?___
A. VXLAN
B. ERSPAN
C. RSPAN
D. SPAN
【单选题】
What are the minimum hardware requirements for a Windows vCenter Server with embedded PSC that manages a “Small” environment?___
A. 2vCPUs, 16 GB RAM
B. 4 vCPUs, 16 GB RAM
C. 2 vCPUs, 10 GB RAM
D. 4 vCPUs, 10 GB RAM
推荐试题
【多选题】
根据我国公务员考核制度规定,公务员年度考核被确定为不称职等次的,按照下列规定办理。___
A. 降低一个职务层次任职
B. 一年内不得晋升职务
C. 本考核年度不计算为按年度考核结果晋升级别和级别工资档次的考核年限
D. 予以辞退
E. 不享受年度考核奖金
【多选题】
辞退公务员,是指机关按照法律规定的条件,通过一定的法律程序,在法定的管理权限内作出的解除公务员全部职务关系的法律行为。根据我国公务员法规定,下列选项中,属于具备被辞退的条件是___
A. 在年度考核中被确定为不称职的
B. 不胜任本职工作又不接受其他安排的
C. 旷工一年累计超过三十天的
D. 因单位调整需要缩减编制员额的
E. 不履行公务员义务,不遵守公务员纪律,经教育仍无转变,不适合继续在机关工作,又不宜给予开除处分的
【多选题】
公务员退休是指公务员达到规定的退休年龄,为国家服务到一定的工作年限,或因病残丧失了工作能力,离开工作岗位,依法办理退休手续,由国家给予生活保障,并给予妥善安置和管理。公务员退休方式包括法定退休和自愿退休。下列选项中,不属于自愿退休的条件是___
A. 工作年限满二十年的
B. 工作年限满二十五年的
C. 工作年限满三十年的
D. 距国家规定的退休年龄不足五年,且工作年限满十五年的
E. 距国家规定的退休年龄不足五年,且工作年限满二十年的
【多选题】
公务员回避,是指机关为了保证国家公务员依法执行公务,促进机关的廉政建设,按照法定条件和程序,对公务员所任职务、执行公务和任职地区等方面作出的限制性规定。下列选项中,不属于公务员回避类型的是___
A. 人事回避
B. 任职回避
C. 公务回避
D. 地域回避
E. 工作回避
【多选题】
公务员职务升降是公务员职务晋升和降职的统称。建立和完善公务员职务升降制度的重要意义主要有___
A. 有利于优化公务员队伍
B. 有利于激励公务员不断进取
C. 有利于公务员队伍的稳定
D. 有利于提高公务员素质
E. 有利于促进机关人和事的结合
【多选题】
公务员奖惩制度,是公务员奖励制度和惩戒制度的合称。公务员管理机构对工作表现突出,有显著成绩和贡献,或者有其他突出事迹的公务员或者公务员集体,给予奖励。公务员或者公务员集体有下列情形之一的,给予奖励。___
A. 忠于职守,积极工作,成绩显著的
B. 遵守纪律,廉洁奉公,作风正派,办事公道,模范作用突出的
C. 在工作中有发明创造或者提出合理化建议,取得显著经济效益或者社会效益的
D. 为增进民族团结、维护社会稳定做出突出贡献的
E. 爱护公共财产,节约国家资财有突出成绩的
【多选题】
公务员的交流,是指机关根据工作需要或公务员个人意愿,通过法定形式,在机关内部调整公务员的工作职位,或者把公务员调出机关任职,或者将机关以外的工作人员调入机关担任公务员职务的管理活动。下列选项中,属于我国公务员交流的范围是___
A. 国有企事业单位
B. 公务员队伍内部
C. 社会自治组织
D. 社会行业协会
E. 从事公务的群众团体
【多选题】
公务员的交流,是指机关根据工作需要或公务员个人意愿,通过法定形式,在机关内部调整公务员的工作职位,或者把公务员调出机关任职,或者将机关以外的工作人员调入机关担任公务员职务的管理活动。公务员交流的基本原则主要有___
A. 依法交流的原则
B. 相对稳定与合理交流的原则
C. 科学用人的原则
D. 注重工作实绩原则
E. 工作需要与个人志愿相结合的原则
【多选题】
辞退公务员,是指机关按照法律规定的条件,通过一定的法律程序,在法定的管理权限内作出的解除公务员全部职务关系的法律行为。但辞退有限制性规定。根据我国公务员法的规定,对有下列情形之一的公务员,不得辞退___
A. 因公致残,被确认丧失或者部分丧失工作能力的
B. 患病或者负伤,在规定的医疗期内的
C. 女性公务员在孕期、产假、哺乳期内的
D. 年度考核中,连续两年被确定为不称职的
E. 法律、行政法规规定的其他不得辞退的情形
【多选题】
公务员职务任免与升降在公务员管理中的作用是___
A. 保证机关中各个职位获得适宜人选的主要途径
B. 一种有效的激励手段
C. 为公务员管理的其他环节提供了管理基础
D. 实现职务管理的保证
E. 实现公务员管理制度化的重要措施
【多选题】
公务员因工作严重失误、失职辞去领导职务的类型有___
A. 因公辞职
B. 因病辞职
C. 自愿辞职
D. 引咎辞职
E. 责令辞职
【多选题】
我国公务员辞职的限制性条件包括___
A. 未满国家规定的最低服务年限
B. 在涉及国家秘密等特殊岗位上任职
C. 重要公务尚未处理完毕,且须由本人继续处理
D. 正在接受审计、纪律审查,或者涉嫌犯罪,司法程序尚未结束
E. 法律规定不得辞职的其他情形
【多选题】
根据我国公务员法的规定,我国公务员处分的种类有___
A. 警告
B. 记过
C. 罚款
D. 降级
E. 撤职
【多选题】
市工商局某公务员提出控告,受理的机关可以是___
A. 市委
B. 市政府
C. 市法院
D. 市行政监察局
E. 市公安局
【多选题】
下列选项中,属于公务员纪律的是___
A. 不得玩忽职守
B. 不得压制批评
C. 不得弄虚作假
D. 不得参加非法组织
E. 不得参加罢工
【多选题】
下列选项中,不属于我国公务员任用坚持的原则是___
A. 监督约束与激励保障并重原则
B. 任人唯贤、德才兼备原则
C. 实行分类管理原则
D. 注重工作实绩原则
E. 提高管理效能原则
【多选题】
某政府机关是一个只有二十多个人的小部门,在过去几年的年度考核中,从未有公务员被定为不称职。但在今年的年度考核中,机关领导动真格了,有一位一向在机关里能说会道、上下左右都能应酬的副科级公务员小王的年度考核结果被确定为不称职,这可以说是某机关近日来的一条新闻。不过,令一些机关公务员不理解的是,小王实在也不是那种思想政治素质不好、没有能力、不会做事的人。譬如说,在每次的政治学习时,小王总是积极发言,他经常自称是最能理解党的方针政策的人,而且他一向表示,他坚决拥护党的路线、方针和政策,事实上他也没有任何政治上不成熟的表现。在工作能力和业务水平方面,他也有一定基础,平时上班也不迟到、不早退。唯一不足的是,与其他少数年轻人一样,他往往好高骛远,眼高手低,因而大事做不来,小事又不做,缺乏工作责任心和责任感,所以尽管他具有一定的工作基础,但是却往往做不出工作绩效,完不成工作任务。然而无论如何,一些人认为他被定为不称职似乎有些过分。小王本人对此人事处理决定也不服,向有关部门提出了申诉。根据公务员申诉的规定,下列说法中,正确的有___
A. 小王对涉及本人的人事处理决定不服,可以向原处理机关申请复核
B. 小王对涉及本人的人事处理决定不服,也可以向同级人民政府人事部门提出申诉
C. 小王对涉及本人的人事处理决定不服,也可以向上级人民政府人事部门提出申诉
D. 小王对涉及本人的人事处理决定不服,也可以向同级行政监察机关提出申诉
E. 小王对涉及本人的人事处理决定不服,也可以向上级行政监察机关提出申诉
【多选题】
地方政府的职能主要是___
A. 宏观调控
B. 公共服务
C. 市场监管
D. 社会管理
E. 环境保护
【多选题】
行政决策特点正确说法是___
A. 行政决策的主体是各级行政机关及其公务员
B. 行政决策的客体是国家政务
C. 行政决策具有法定性
D. 行政决策具有公共性和公平性
E. 行政决策具有执行力
【多选题】
各政府之间和各部门之间的相互关系可以是___
A. 行政领导关系
B. 业务指导关系
C. 条条块块关系
D. 分工协作关系
E. 双重领导关系
【多选题】
十八届四中全会明确提出重大行政决策法定程序应当确定为___
A. 公众参与
B. 专家论证
C. 风险评估
D. 合法性审查
E. 集体讨论决定
【多选题】
行政决策具有如下原则___
A. 目标原则
B. 信息原则
C. 预测原则
D. 择优原则
E. 稳定原则
【多选题】
机关管理活动其功能有___
A. 决策功能
B. 执行功能
C. 指挥功能
D. 协调功能
E. 监督功能以及控制功能
【多选题】
决策的可行性是指___
A. 决策时充分考虑相关的人力、物力和财力的承受条件
B. 决策留有余地,保持可调节的弹性
C. 充分尊重上级部门的意见
D. 充分尊重其他部门的意见
E. 信息的真实性
【多选题】
行政决策方面的问题包含两种情况___
A. 消极意义上的问题,即现有状况偏离了正常状态
B. 保持现有的状况
C. 防止出现偏差
D. 市场价格的波动
E. 积极意义上的问题,可以争取更理想结果的状态
【多选题】
制定行政计划要遵循以下基本要求___
A. 符合决策意图
B. 内容切实可行
C. 综合平衡
D. 原则的坚定性与策略的灵活性
E. 统筹兼顾
【多选题】
实现行政决策的公共性和公平性必须___
A. 民主原则
B. 科学原则
C. 集体原则
D. 发展原则
E. 和谐原则
【多选题】
决策的动态过程一般是___
A. 发现问题,确定目标
B. 精心设计,拟定方案
C. 及时总结,严格考核
D. 分析评估,方案择优
E. 实施方案,追踪决策
【多选题】
国民经济计划包括___
A. 社会总产品和国民收人计划
B. 工农业生产计划
C. 商品流通计划
D. 人口和劳动力计划
E. 社会保障计划
【多选题】
机关工作计划按管理层次可分为___
A. 中央计划
B. 地方计划
C. 基层计划
D. 年度计划
E. 部门计划
【多选题】
工作总结的基本方法___
A. 民主的、群众性的总结方法
B. 自下而上和自上而下相结合的总结方法
C. 年度总结的方法
D. 领导亲自动手的总结方法
E. 季度总结的方法
【多选题】
计划的制定过程包括___
A. 情况的调查与分析
B. 确定目标
C. 拟定计划备选方案
D. 评估备选方案
E. 选择更优方案
【多选题】
选择最终计划方案主要是看___
A. 哪一个最为接近许可条件
B. 符合计划目标的要求
C. 哪一个目标最高
D. 哪一个成本最低
E. 风险相对最小和比较确定
【多选题】
执行的结果可以判断出___
A. 一个政府部门是否圆满地完成决策目标
B. 检验政府组织机构设置和权力配置是否合理
C. 行政领导和公务员素质是否体现
D. 具体工作制度是否健全
E. 信息反馈系统和检查监督系统的工作是否得力
【多选题】
行政执行就是___
A. 行政机关和公务员完成上级指令的过程
B. 实施行政计划的行政管理活动
C. 它是行政工作程序中紧接行政计划之后的一个环节
D. 是各级行政机关将决策付诸实施的过程
E. 直接与行政相对人接触的政府管理活动
【多选题】
机关工作执行具有以下特点___
A. 机关工作执行是一种具有目标导向的活动
B. 机关工作执行是各级政府及公务员的日常活动
C. 机关工作执行是一种强制活动
D. 机关工作执行是一种具有时限要求的活动
E. 机关工作执行是具有连续性的活动
【多选题】
决策能不能执行的外部条件是___
A. 人民群众对决策目标的认同和支持的程度
B. 社会的经济水平、文明程度
C. 社会的政治状况
D. 周边环境的影响
E. 决策的科学性
【多选题】
执行前的准备阶段___
A. 思想准备
B. 组织准备
C. 财务准备
D. 理论准备
E. 法律准备
【多选题】
影响行政执行主体状况的要素包括___
A. 行政执行机构的设置和运作是否相适应
B. 领导是否得力
C. 人员的配置和素质是否合适
D. 技术力量
E. 财力物力
【多选题】
组织准备包括___
A. 建立组织机构
B. 配备胜任的负责人和公务员
C. 确定职位、职责、职权,进行有效的指挥
D. 协调相互关系
E. 建立简便的工作程序与办事制度