儲存體複本概觀Storage Replica overview

適用於:Windows Server (半年度管道)、Windows Server 2016Applies to: Windows Server (Semi-Annual Channel), Windows Server 2016

「儲存體複本」是一種 Windows Server 技術,可在伺服器或叢集之間啟用磁碟區複寫來進行災害復原。Storage Replica is Windows Server technology that enables replication of volumes between servers or clusters for disaster recovery. 它也可讓您建立跨兩個網站的延展式容錯移轉叢集,並且保持所有節點同步。It also enables you to create stretch failover clusters that span two sites, with all nodes staying in sync.

儲存體複本支援同步和非同步複寫︰Storage Replica supports synchronous and asynchronous replication:

  • 同步複寫會以當機時保持一致的磁碟區鏡像低延遲網站內的資料,確保檔案系統層級在失敗期間零資料遺失。Synchronous replication mirrors data within a low-latency network site with crash-consistent volumes to ensure zero data loss at the file-system level during a failure.
  • 非同步複寫會透過延遲較高的網路連結來鏡像跨非都會範圍之網站的資料,但不保證兩個網站在失敗時具有相同的資料複本。Asynchronous replication mirrors data across sites beyond metropolitan ranges over network links with higher latencies, but without a guarantee that both sites have identical copies of the data at the time of a failure.

本指南概要說明您的企業如何受益於這項新功能,以及儲存體複本支援的不同複寫案例。This guide outlines how your business can benefit from this new functionality and the different replication scenarios that are supported by Storage Replica. 這裡假設您先前有 Windows Server、容錯移轉叢集、檔案伺服器和 Hyper-V 的作業知識,包含基本的系統管理。It assumes that you have a previous working knowledge of Windows Server, Failover Clustering, File Servers, and Hyper-V, to include basic administration.

為什麼要使用儲存體複本?Why use Storage Replica?

儲存體複本在 Windows Server 2016 Datacenter Edition 中提供新的災害復原和準備功能。Storage Replica offers new disaster recovery and preparedness capabilities in Windows Server 2016 Datacenter Edition. Windows Server 首次提供了令人高枕無憂的零資料遺失功能,並能夠同步地保護位於不同機架、樓層、建築物、校區及縣市的資料。For the first time, Windows Server offers the peace of mind of zero data loss, with the ability to synchronously protect data on different racks, floors, buildings, campuses, counties, and cities. 在發生災害事件後,所有資料都會存在其他地方,而不會有遺失的可能。After a disaster strikes, all data will exist elsewhere without any possibility of loss. 這同樣適用於發生災害事件「之前」的情況。儲存體複本可讓您在災害發生之前接獲警告,並將工作負載切換到安全的位置,而避免遺失任何資料。The same applies before a disaster strikes; Storage Replica offers you the ability to switch workloads to safe locations prior to catastrophes when granted a few moments warning - again, with no data loss.

儲存體複本允許更有效率地使用多個資料中心。Storage Replica allows more efficient use of multiple datacenters. 藉由延伸叢集或複寫叢集,便可以在多個資料中心執行工作負載,使當地鄰近的使用者和應用程式能夠更快速地存取資料,以及更妥善地分散負載並使用運算資源。By stretching clusters or replicating clusters, workloads can be run in multiple datacenters for quicker data access by local proximity users and applications, as well as better load distribution and use of compute resources. 如果發生的災害使得其中一個資料中心離線,您可以將它的一般工作負載暫時移到其他站台。If a disaster takes one datacenter offline, you can move its typical workloads to the other site temporarily.

儲存體複本可讓您將被迫充當低階災害復原解決方案的現有檔案複寫系統 (例如 DFS 複寫) 進行解除委任。Storage Replica may allow you to decommission existing file replication systems such as DFS Replication that were pressed into duty as low-end disaster recovery solutions. 雖然 DFS 複寫在極低頻寬網路上的運作良好,但其延遲非常高,通常長達數小時或數天。While DFS Replication works well over extremely low bandwidth networks, its latency is very high - often measured in hours or days. 這是由 DFSR 要求將檔案關閉所造成,而它人為節流的目的則是為了防止網路壅塞。This is caused by its requirement for files to close and its artificial throttles meant to prevent network congestion. 由於那些特性,DFS 複寫複本中最新且最熱門的檔案,是最不可能被複寫的。With those design characteristics, the newest and hottest files in a DFS Replication replica are the least likely to replicate. 儲存體複本是在檔案層級之下運作,而且沒有這些限制。Storage Replica operates below the file level and has none of these restrictions.

儲存體複本也針對範圍較遠及延遲較高的網路支援非同步複寫。Storage Replica also supports asynchronous replication for longer ranges and higher latency networks. 它不是以檢查點為基礎,而是會持續地進行複寫,因此變更差異通常遠低於以快照為基礎的產品。Because it is not checkpoint-based, and instead continuously replicates, the delta of changes will tend to be far lower than snapshot-based products. 此外,儲存體複本是在資料分割層運作,因此會複寫 Windows Server 或備份軟體所建立的所有 VSS 快照;這將允許針對時間點復原使用應用程式一致的資料快照,特別是以非同步方式複寫的非結構化使用者資料。Furthermore, Storage Replica operates at the partition layer and therefore replicates all VSS snapshots created by Windows Server or backup software; this allows use of application-consistent data snapshots for point in time recovery, especially unstructured user data replicated asynchronously.

支援的設定Supported configurations

您可以使用本指南和 Windows Server 2016 Datacenter Edition,在延展式叢集中、叢集對叢集之間,以及伺服器對伺服器設定中部署儲存體複寫 (請參閱圖 1-3)。Using this guide and Windows Server 2016 Datacenter Edition, you can deploy storage replication in a stretch cluster, between cluster-to-cluster, and in server-to-server configurations (see Figures 1-3).

「延展式叢集」允許在單一叢集中設定電腦與儲存體,其中某些節點會共用一組非對稱式儲存體,而其他節點則會共用另一組非對稱式儲存體,並會以同步或非同步的方式搭配網站感知進行複寫。Stretch Cluster allows configuration of computers and storage in a single cluster, where some nodes share one set of asymmetric storage and some nodes share another, then synchronously or asynchronously replicate with site awareness. 此案例可以運用具有共用 SAS 儲存體、SAN 和連接 iSCSI 的 LUN 的儲存空間。This scenario can utilize Storage Spaces with shared SAS storage, SAN and iSCSI-attached LUNs. 它是以 PowerShell 和容錯移轉叢集管理員圖形工具進行管理,而且允許自動化的工作負載容錯移轉。It is managed with PowerShell and the Failover Cluster Manager graphical tool, and allows for automated workload failover.

這個圖表顯示紐約州兩個使用儲存體複本的叢集節點如何與紐澤西州的兩個節點複寫儲存體

圖 1︰使用儲存體複本在延展式叢集中進行儲存體複寫FIGURE 1: Storage replication in a stretch cluster using Storage Replica

「叢集對叢集」允許在兩個不同的叢集之間複寫,其中某個叢集會以同步或非同步的方式與另一個叢集進行複寫。Cluster to Cluster allows replication between two separate clusters, where one cluster synchronously or asynchronously replicates with another cluster. 此案例可以運用具有共用 SAS 儲存體、SAN 和連接 iSCSI 的 LUN 的儲存空間直接存取和儲存空間。This scenario can utilize Storage Spaces Direct, Storage Spaces with shared SAS storage, SAN and iSCSI-attached LUNs. 它是使用 PowerShell 加以管理,而且針對容錯移轉需要手動介入。It is managed with PowerShell and requires manual intervention for failover. 此案例的Azure Site Recovery 支援已排程。Support for Azure Site Recovery of this scenario is scheduled.

這個圖表顯示洛杉磯使用儲存體複本的叢集如何與拉斯維加斯的不同叢複寫其儲存體

圖 2︰使用儲存體複本進行叢集對叢集儲存體複寫FIGURE 2: Cluster-to-cluster storage replication using Storage Replica

伺服器對伺服器允許在兩個獨立伺服器之間,使用具有共用 SAS 儲存體、SAN 和連接 iSCSI 的 LUN 的儲存空間以及本機磁碟機,進行同步和非同步複寫。Server to server allows synchronous and asynchronous replication between two standalone servers, using Storage Spaces with shared SAS storage, SAN and iSCSI-attached LUNs, and local drives. 它是使用 PowerShell 和伺服器管理員工具加以管理,而且針對容錯移轉需要手動介入。It is managed with PowerShell and the Server Manager Tool, and requires manual intervention for failover.

這個圖表顯示與建築物 9 的伺服器進行複寫之建築物 5 的伺服器

圖 3︰使用儲存體複本進行伺服器對伺服器儲存體複寫FIGURE 3: Server-to-server storage replication using Storage Replica

注意

您也可以在一部電腦上使用四個不同的磁碟區,設定伺服器對自我複寫。You can also configure server-to-self replication, using four separate volumes on one computer. 不過,本指南並未涵蓋此案例。However, this guide does not cover this scenario.

儲存體複本功能 Storage Replica Features

  • 零資料遺失、區塊層級的複寫Zero data loss, block-level replication. 使用同步複寫時,不可能會發生資料遺失。With synchronous replication, there is no possibility of data loss. 使用區塊層級的複寫時,不可能會發生檔案鎖定。With block-level replication, there is no possibility of file locking.

  • 簡單的部署和管理Simple deployment and management. 儲存體複本具有容易使用的設計。Storage Replica has a design mandate for ease of use. 在兩部伺服器之間建立複寫合作關係,只需一個 PowerShell 命令。Creation of a replication partnership between two servers requires only a single PowerShell command. 部署延展式叢集時,會使用熟悉的容錯移轉叢集管理員工具中的直覺式精靈。Deployment of stretch clusters uses intuitive wizard in the familiar Failover Cluster Manager tool.

  • 客體和主機Guest and host. 儲存體複本的所有功能都會向虛擬化客體和主機型部署公開。All capabilities of Storage Replica are exposed in both virtualized guest and host-based deployments. 也就是說,即使客體是在非 Windows 的虛擬化平台或公用雲端上執行,只要客體是使用 Windows Server 2016 Datacenter Edition,便可以複寫其資料磁碟區。This means guests can replicate their data volumes even if running on non-Windows virtualization platforms or in public clouds, as long as using Windows Server 2016 Datacenter Edition in the guest.

  • 以 SMB3 為基礎SMB3-based. 儲存體複本會使用經過實證且成熟的 SMB 3 技術,此技術首次是在 Windows Server 2012 中發佈。Storage Replica uses the proven and mature technology of SMB 3, first released in Windows Server 2012. 這表示所有 SMB 的進階特性 (例如 RoCE、iWARP 及 InfiniBand RDMA 網路卡上的多重通道和 SMB 直接傳輸支援) 都可用於儲存體複本。This means all of SMB's advanced characteristics - such as multichannel and SMB direct support on RoCE, iWARP, and InfiniBand RDMA network cards - are available to Storage Replica.

  • 安全性Security. 與許多廠商的產品不同,儲存體複本具備領先業界的安全性技術。Unlike many vendor's products, Storage Replica has industry-leading security technology baked in. 這包括封包簽署、AES-128-GCM 完整資料加密、Intel AES NI 加密加速的支援,以及預先驗證完整性攔截式攻擊預防。This includes packet signing, AES-128-GCM full data encryption, support for Intel AES-NI encryption acceleration, and pre-authentication integrity man-in-the-middle attack prevention. 儲存體複本在節點之間利用 Kerberos AES256 進行所有驗證。Storage Replica utilizes Kerberos AES256 for all authentication between nodes.

  • 高效能的初始同步。儲存體複本支援已植入的初始同步,其中資料的子集已經存在於舊版複本、備份,或隨附磁碟機的目標上。High performance initial sync. Storage Replica supports seeded initial sync, where a subset of data already exists on a target from older copies, backups, or shipped drives. 初始複寫只會複製不同的區塊,這可能會縮短初始同步時間,並防止資料用盡有限的頻寬。Initial replication will only copy the differing blocks, potentially shortening initial sync time and preventing data from using up limited bandwidth. 儲存體複本會封鎖總和檢查碼計算和彙總,也就是說,初始同步效能只會受到儲存體和網路速度的限制。Storage replicas block checksum calculation and aggregation means that initial sync performance is limited only by the speed of the storage and network.

  • 一致性群組Consistency groups. 寫入順序可保證 Microsoft SQL Server 之類的應用程式可以寫入至多個複寫的磁碟區,並知道資料會在目的地伺服器上循序寫入。Write ordering guarantees that applications such as Microsoft SQL Server can write to multiple replicated volumes and know the data will write on the destination server sequentially.

  • 使用者委派User delegation. 不是區域複寫節點上內建系統管理員群組成員的使用者,可以取得委派權限以管理複寫,這將能限制該使用者對於不相關區域的存取。Users can be delegated permissions to manage replication without being a member of the built-in Administrators group on the replicated nodes, therefore limiting their access to unrelated areas.

  • 網路限制Network Constraint. 儲存體複本可依伺服器和複寫的磁碟區,限制為個別的網路,以提供應用程式、備份和管理軟體頻寬。Storage Replica can be limited to individual networks by server and by replicated volumes, in order to provide application, backup, and management software bandwidth.

  • 精簡佈建Thin provisioning. 支援儲存空間和 SAN 裝置的精簡佈建,以在許多情況下提供接近即時的初始複寫時間。Support for thin provisioning in Storage Spaces and SAN devices is supported, in order to provide near-instantaneous initial replication times under many circumstances.

Windows Server 2016 會在儲存體複本中實作下列功能︰Windows Server 2016 implements the following features in Storage Replica:

功能Feature 詳細資料Details
類型Type 主機型Host-based
同步Synchronous Yes
非同步Asynchronous Yes
儲存硬體無關Storage hardware agnostic Yes
複寫單位Replication unit 磁碟區 (磁碟分割)Volume (Partition)
建立 Windows Server 延展式叢集Windows Server Stretch Cluster creation Yes
伺服器對伺服器複寫Server to server replication Yes
叢集對叢集複寫Cluster to cluster replication Yes
傳輸Transport SMB3SMB3
網路Network TCP/IP 或 RDMATCP/IP or RDMA
網路限制支援Network constraint support Yes
RDMARDMA iWARP、InfiniBand、RoCE v2iWARP, InfiniBand, RoCE v2
複寫網路連接埠防火牆需求Replication network port firewall requirements 單一 IANA 連接埠 (TCP 445 或 5445)Single IANA port (TCP 445 or 5445)
多重路徑/多重通道Multipath/Multichannel 是 (SMB3)Yes (SMB3)
Kerberos 支援Kerberos support 是 (SMB3)Yes (SMB3)
透過連線加密和簽署Over the wire encryption and signing 是 (SMB3)Yes (SMB3)
允許個別磁碟區容錯移轉Per-volume failovers allowed Yes
精簡佈建的儲存體支援Thin-provisioned storage support Yes
隨附管理 UIManagement UI in-box PowerShell、容錯移轉叢集管理員PowerShell, Failover Cluster Manager

可能需要更長的運輸設備及纜線。May require additional long haul equipment and cabling.

儲存體複本先決條件 Storage Replica Prerequisites

  • Active Directory Domain Services 樹系。Active Directory Domain Services forest.
  • 具有 SAS JBOD、儲存空間直接存取、光纖通道 SAN、共用 VHDX、iSCSI 目標或本機 SAS/SCSI/SATA 儲存體的儲存空間。Storage Spaces with SAS JBODs, Storage Spaces Direct, fibre channel SAN, shared VHDX, iSCSI Target, or local SAS/SCSI/SATA storage. 針對複寫記錄檔磁碟機,建議使用 SSD 或更快的裝置。SSD or faster recommended for replication log drives. Microsoft 建議記錄檔儲存體應該要比資料儲存體更快。Microsoft recommends that the log storage be faster than the data storage. 記錄檔磁碟區不得用於其他工作負載。Log volumes must never be used for other workloads.
  • 每部伺服器上至少要有一個乙太網路/TCP 連線,以進行同步複寫,但最好是 RDMA。At least one ethernet/TCP connection on each server for synchronous replication, but preferably RDMA.
  • 每部伺服器至少要有 2 GB 的 RAM 和兩個核心。At least 2GB of RAM and two cores per server.
  • 針對同步複寫,伺服器間的網路頻寬必須足以容納您的 IO 寫入工作負載,以及平均 5 毫秒以下的來回延遲。A network between servers with enough bandwidth to contain your IO write workload and an average of 5ms round trip latency or lower, for synchronous replication. 非同步複寫沒有建議的延遲值。Asynchronous replication does not have a latency recommendation.

背景 Background

本節包含高階業界術語、同步和非同步複寫和重要行為的相關資訊。This section includes information about high-level industry terms, synchronous and asynchronous replication, and key behaviors.

高階業界術語High level industry terms

災害復原 (DR) 指的是從網站災害中復原,使企業能夠繼續運作的緊急應變計畫。Disaster Recovery (DR) refers to a contingency plan for recovering from site catastrophes so that the business continues to operate. 資料 DR 表示位於不同實體位置中的多個生產資料複本。Data DR means multiple copies of production data in a separate physical location. 其中一個例子為延展式叢集,其半數的節點位於一個站台,而另一半則位於另一個站台。For example, a stretch cluster, where half the nodes are in one site and half are in another. 災害準備 (DP) 指的是在災害 (例如颶風) 即將到來之前,先將工作負載移到不同位置的緊急應變計畫。Disaster Preparedness (DP) refers to a contingency plan for preemptively moving workloads to a different location prior to an oncoming disaster, such as a hurricane.

服務等級協定 (SLA) 定義企業應用程式在已計畫和未計畫中斷期間的可用性,以及對於停機時間和資料遺失的容忍度。Service level agreements (SLAs) define the availability of a business' applications and their tolerance of down time and data loss during planned and unplanned outages. 復原時間目標 (RTO) 定義企業可以容忍完全無法存取資料的時間長度。Recovery Time Objective (RTO) defines how long the business can tolerate total inaccessibility of data. 復原點目標 (RPO) 定義企業可以容忍遺失的資料量。Recovery Point Objective (RPO) defines how much data the business can afford to lose.

同步複寫Synchronous Replication

同步複寫可保證應用程式在完成 IO 前,將資料同時寫入至兩個位置。Synchronous replication guarantees that the application writes data to two locations at once before completion of the IO. 此複寫更適合任務關鍵資料,因為它需要對網路和儲存體做出投資,也會有應用程式效能降低的風險。This replication is more suitable for mission critical data, as it requires network and storage investments, as well as a risk of degraded application performance.

當應用程式寫入在來源資料複本上發生時,原始儲存體將不會立即確認 IO。When application writes occur on the source data copy, the originating storage does not acknowledge the IO immediately. 相反地,那些資料變更會複寫到遠端目的地複本並傳回確認。Instead, those data changes replicate to the remote destination copy and return an acknowledgement. 只有在那時,應用程式才會接收到 IO 確認。Only then does the application receive the IO acknowledgment. 這可確保遠端站台與來源站台持續同步處理,因而將儲存體 IO 延伸到整個網路。This ensures constant synchronization of the remote site with the source site, in effect extending storage IOs across the network. 如果來源站台失敗,應用程式可以容錯移轉至遠端站台,並繼續執行其作業並保證零資料遺失。In the event of a source site failure, applications can failover to the remote site and resume their operations with assurance of zero data loss.

模式Mode 圖表Diagram 步驟Steps
同步Synchronous

零資料遺失Zero Data Loss

RPORPO
這個圖表顯示儲存體複本如何在同步複寫中寫入資料 1.應用程式寫入資料1. Application writes data
2.記錄檔資料已寫入,且資料已複寫至遠端站台2. Log data is written and the data is replicated to the remote site
3.記錄檔資料已在遠端站台寫入3. Log data is written at the remote site
4.遠端站台做出確認4. Acknowledgement from the remote site
5.應用程式寫入已確認5. Application write acknowledged

t & t1︰資料排清到磁碟區,記錄檔一律寫入t & t1 : Data flushed to the volume, logs always write through

非同步複寫Asynchronous Replication

相反地,非同步複寫表示當應用程式寫入資料時,該資料會複寫至遠端站台,且不保證會立即做出確認。Contrarily, asynchronous replication means that when the application writes data, that data replicates to the remote site without immediate acknowledgment guarantees. 此模式允許應用程式更快的回應時間,以及能夠跨地理位置運作的 DR 解決方案。This mode allows faster response time to the application as well as a DR solution that works geographically.

當應用程式寫入資料時,複寫引擎會擷取寫入,並立即向應用程式確認。When the application writes data, the replication engine captures the write and immediately acknowledges to the application. 接著,擷取的資料會複寫至遠端位置。The captured data then replicates to the remote location. 遠端節點會處理資料的複本,並延遲向來源複本做出確認。The remote node processes the copy of the data and lazily acknowledges back to the source copy. 由於複寫效能已不再位於應用程式 IO 路徑中,因此遠端站台的回應速度和距離等因素將變得較不重要。Since replication performance is no longer in the application IO path, the remote site's responsiveness and distance are less important factors. 這在來源資料遺失,而該資料的目的地複本仍在緩衝區且尚未離開來源時,將會有資料遺失的風險。There is risk of data loss if the source data is lost and the destination copy of the data was still in buffer without leaving the source.

由於非同步複寫具有高於零的 RPO,因此比較不適合做為容錯移轉叢集之類的 HA 解決方案,因為它們是針對具有備援能力且不會遺失資料的連續作業而設計。With its higher than zero RPO, asynchronous replication is less suitable for HA solutions like Failover Clusters, as they are designed for continuous operation with redundancy and no loss of data.

模式Mode 圖表Diagram 步驟Steps
非同步Asynchronous

接近零的資料遺失Near zero data loss

(取決於多個因素)(depends on multiple factors)

RPORPO
這個圖表顯示儲存體複本如何在非同步複寫中寫入資料 1.應用程式寫入資料1. Application writes data
2.記錄檔資料已寫入2. Log data written
3.應用程式寫入已確認3. Application write acknowledged
4.資料複寫到遠端站台4. Data replicated to the remote site
5.記錄檔資料已在遠端站台寫入5. Log data written at the remote site
6.遠端站台做出確認6. Acknowledgement from the remote site

t & t1︰資料排清到磁碟區,記錄檔一律寫入t & t1 : Data flushed to the volume, logs always write through

關鍵評估重點和行為Key Evaluation Points and Behaviors

  • 使用最快儲存體的網路頻寬和延遲:Network bandwidth and latency with fastest storage. 同步複寫有一些相關的實體限制。There are physical limitations around synchronous replication. 由於儲存體複本會使用記錄檔實作 IO 篩選機制,並需要進行網路往返,因此同步複寫可能會讓應用程式寫入更慢。Because Storage Replica implements an IO filtering mechanism using logs and requiring network round trips, synchronous replication is likely make application writes slower. 透過針對記錄檔使用低延遲、高頻寬網路,以及高輸送量的磁碟子系統,您可將效能負擔降至最低。By using low latency, high-bandwidth networks as well as high-throughput disk subsystems for the logs, you will minimize performance overhead.

  • 在 Windows Server 2016 中複寫時,將無法存取目的地磁碟區。The destination volume is not accessible while replicating in Windows Server 2016. 當您設定複寫時,目的地磁碟區將會卸載,進而讓使用者無法進行任何讀取或寫入。When you configure replication, the destination volume dismounts, making it inaccessible to any reads or writes by users. 其磁碟機代號可能會顯示在一般介面上,例如檔案總管,但應用程式無法存取磁碟區本身。Its driver letter may be visible in typical interfaces like File Explorer, but an application cannot access the volume itself. 區塊層級的複寫技術不相容於允許對目的地目標位於磁碟區中已掛接的檔案系統進行存取;NTFS 和 ReFS 不支援使用者在區塊變更期間將資料寫入至磁碟區。Block-level replication technologies are incompatible with allowing access to the destination target's mounted file system in a volume; NTFS and ReFS do not support users writing data to the volume while blocks change underneath them.

Windows Server 版本 1709 已加入新的 [測試容錯移轉] 選項。In Windows Server, Version 1709 the new Test-Failover option was added. 此選項現在暫時支援掛接目的地磁碟區讀寫快照集,以供進行備份、測試等。如需詳細資訊,請參閱 https://aka.ms/srfaq。This now supports temporarily mounting a read-write snapshot of the destination volume for backups, testing, etc. See https://aka.ms/srfaq for more info.

  • Microsoft 非同步複寫的實作與大多數實作不同:The Microsoft implementation of asynchronous replication is different than most. 業界大部分的非同步複寫實作依賴以快照為基礎的複寫,其中定期的差異傳輸會移到其他節點並合併。Most industry implementations of asynchronous replication rely on snapshot-based replication, where periodic differential transfers move to the other node and merge. 儲存體複本的非同步複寫的運作方式和同步複寫相同,唯一不同之處在於它移除了目的地進行序列化同步通知的需求。Storage Replica asynchronous replication operates just like synchronous replication, except that it removes the requirement for a serialized synchronous acknowledgment from the destination. 也就是說,儲存體複本的 RPO 在理論上會比較低,因為它會連續複寫。This means that Storage Replica theoretically has a lower RPO as it continuously replicates. 不過,這也表示它會依賴內部應用程式的一致性保證,而不是使用快照在應用程式檔案中強制執行一致性。However, this also means it relies on internal application consistency guarantees rather than using snapshots to force consistency in application files. 儲存體複本可以在所有複寫模式中保證絕對一致性Storage Replica guarantees crash consistency in all replication modes

  • 許多客戶使用 DFS 複寫作為災害復原解決方案,雖然 DFSR 對於該案例通常並不實用,因為 DFS 複寫無法複寫已開啟的檔案,且其設計是犧牲效能來將頻寬使用量降至最低,進而導致大量的復原點差異。Many customers use DFS Replication as a disaster recovery solution even though often impractical for that scenario - DFS Replication cannot replicate open files and is designed to minimize bandwidth usage at the expense of performance, leading to large recovery point deltas. 儲存體複本可讓您將 DFS 複寫從上述部分類型的災害復原責任中淘汰。Storage Replica may allow you to retire DFS Replication from some of these types of disaster recovery duties.

  • 儲存體複本不是備份:Storage Replica is not backup. 相較於每日備份,某些 IT 環境基於複寫系統的零資料遺失選項,會將複寫系統部署為備份解決方案。Some IT environments deploy replication systems as backup solutions, due to their zero data loss options when compared to daily backups. 儲存體複本會將所有資料區塊的變更複寫到磁碟區上,無論該變更的類型為何。Storage Replica replicates all changes to all blocks of data on the volume, regardless of the change type. 如果有使用者將磁碟區中的資料全數刪除,儲存體複本會將該刪除立即複寫到其他磁碟區,進而將兩部伺服器中的資料同時移除,而且無法變更。If a user deletes all data from a volume, Storage Replica will replicate the deletion instantly to the other volume, irrevocably removing the data from both servers. 請不要使用儲存體複本作為時間點備份解決方案的替代方案。Do not use Storage Replica as a replacement for a point-in-time backup solution.

  • 儲存體複本不是 Hyper-V 複本或 Microsoft SQL AlwaysOn 可用性群組:Storage Replica is not Hyper-V Replica or Microsoft SQL AlwaysOn Availability Groups. 儲存體複本是一個一般用途,且與儲存體無關的引擎。Storage Replica is a general purpose, storage-agnostic engine. 根據定義,它無法將其行為量身打造為應用程式層級的複寫。By definition, it cannot tailor its behavior as ideally as application-level replication. 這可能會導致特定功能差距,這些差距會讓您想要部署或繼續使用特定應用程式複寫技術。This may lead to specific feature gaps that encourage you to deploy or remain on specific application replication technologies.

注意

本文件包含已知問題和預期行為的清單,以及常見問題集小節。This document contains a list of known issues and expected behaviors as well as Frequently Asked Questions section.

儲存體複本術語Storage Replica terminology

本指南會經常使用下列術語︰This guide frequently uses the following terms:

  • 「來源」是允許本機寫入,且會向外複寫的電腦磁碟區。The source is a computer's volume that allows local writes and replicates outbound. 也稱為「主要」。Also known as "primary".

  • 「目的地」是不允許本機寫入,且會向內複寫的電腦磁碟區。The destination is a computer's volume that does not allow local writes and replicates inbound. 也稱為「次要」。Also known as "secondary".

  • 「複寫合作關係」是來源電腦和目的地電腦之間,針對一或多個磁碟區的同步處理關係,並會運用單一記錄檔。A replication partnership is the synchronization relationship between a source and destination computer for one or more volumes and utilizes a single log.

  • 「複寫群組」是以個別伺服器為基礎,於相同合作關係內的磁碟區及其複寫設定的組織。A replication group is the organization of volumes and their replication configuration within a partnership, on a per server basis. 「群組」可能包含一或多個磁碟區。A group may contain one or more volumes.

另請參閱See also