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Function documentationMicrosoft Cluster Service on Windows Locate this document in the navigation structure

 

The Microsoft Cluster Service (MSCS) configuration is the standard failover solution for the SAP system running on Windows platforms. In this configuration, the SAP system is installed on two or more nodes of a cluster. Under normal operation, the (ABAP) central services ((A)SCS) instance runs on one node and the database on the other node of the cluster. If one of the nodes fails, the affected (A)SCS or database instance is automatically moved to the other node, so preventing downtime. The failover mechanism is enabled by the MSCS software and a cluster-aware version of the database management system (DBMS).

Note Note

“(A)SCS” means either the ABAP central services instance (ASCS) or the Java central services instance (SCS).

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The main advantage of MSCS is that it improves the availability of the system and safeguards it against failure and unplanned downtime.

The cluster is normally fully transparent to clients accessing MSCS. However, there might be a delay in the event of failure due to failure.

Note Note

SAP only supports standard configurations.

For more information about SAP support for MSCS, see SAP Note 106275.

If you want to install a different form of clustering or high-availability solution, contact your SAP partner, who can arrange installation and support.

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MSCS Configuration

Features

With SAP cluster on Windows, SAP offers a standard high-availability solution for the SAP system on all supported hardware platforms. SAP achieves this with the cluster capabilities of MSCS.

Performance during normal installation is comparable to a distributed installation. Automatic failover occurs rapidly without manual intervention, so you lose no time manually working out the cause of the problem and deciding how to fix it.

Activities

During operation of SAP Cluster on Windows platforms, MSCS monitors the system for failure and fails over services in the event of a failure. Both monitoring and switchover occurs automatically, that is, without operator intervention. However, the system administrator is still responsible for solving the problem that led to failure (for example, replacing faulty hardware components).

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