Smart Assist for SAP Netweaver

Smart Assist for SAP Netweaver supports multiple SID installations in which resources are not shared among instances of different SIDs.

In a typical SAP Netweaver installation, the following single point of failures must be protected.

  • SAP global file system
  • SAP ABAP central services instance
  • SAP Java™ central service instance
  • SAP enqueue replication server instance for ABAP
  • SAP enqueue replication server instance for Java
  • Optional: SAP application server instance. If you have only one SAP application server instance, you can set up multiple AS/Dialog instances with SAP application server.
Apart from these SAP Netweaver internal single points of failures, the following components are also important to achieve high availability of SAP Netweaver:
  • Database instance (powered by either IBM® DB2®, Oracle database, or SAP MaxDB)
  • SAP liveCache Hot Standby (optional)

If you are using Network File System version 4 (NFSv4), the application monitor for the SAP Central Service (SCS) instance might time out if the NFS performance is slow. This time out issue can cause an unwanted failover of the SCS instance. To prevent this problem, you can change the lease time for NFSv4 by running the /usr/sbin/chnfs -L'20' '-B' command. You must restart the node for the lease time change to take effect.

The PowerHA® SystemMirror® base version still supports Network File System if it is used to make any application highly available by using a traditional method.

Smart Assist for SAP Netweaver helps you identify a single point of failure with the following features:
Support for standalone Enqueue Server 2

The Central Services Instance ABAP (ASCS) instance and Enqueue Replicator Server (ERS) instance might not run on the same node simultaneously when you are using a standalone Enqueue Server.

During failover of the ASCS instance, if you move the ASCS instance to a host where ERS is running, you must restart all ERS instances. This process results in two recovery actions. The services are unavailable during these recovery actions, which decrease the overall availability of the solution.

With the new standalone Enqueue Server2 (ENSA2) feature, the ASCS can failover to a host where ERS is not running, thus avoiding the need for the ERS instance to be moved.

The ASCS instance can start on any other host in the cluster and retrieve the lock table.

PowerHA SystemMirror supports both standalone Enqueue Server (ENSA) and ENSA2.

Discovers all the configured SAP Netweaver instances such as central services instances and enqueue replication instances that are running in the cluster (collection of nodes) and it's associated resources such as volume groups and logical host names.
Optionally, this feature can be used to configure the SAP Global directory or SAP Transport directory, based on NFS4 and SAP Application Server instances.
Configures different SAP Netweaver instances by creating appropriate PowerHA SystemMirror objects such as resource groups, application servers, application monitor, and service IP addresses.
You can use start and stop monitor scripts to effectively manage SAP Netweaver instances while protecting SAP global file systems through NFS.