SAP HANA SPS06 – Early Revisions upgrade reason.

 Data Consistency Regression in SAP HANA SPS06 – Early Revisions

As part of a proactive landscape stabilization initiative, SAP Enterprise Cloud Services has identified a potential issue, that could lead to unplanned downtime or slow performance or non-compliance. These potential issues are tracked as Top Issues by SAP Enterprise Cloud Services and recommendations are shared with customers to mitigate the risk and avoid any business impact.

 

We are contacting you, because you may have a SAP S/4HANA Cloud system or SAP HANA Enterprise Cloud system impacted by a new Top Issue.

 

Top Issue Description

Due to a programming error in early SAP HANA 2 SPS06 revisions, the complete SAP HANA transaction is being rolled back instead of a rollback on the statement level in case an enterprise search statement was cancelled previously on the same SAP HANA connection. This issue only applies for the following Revisions:

• SAP HANA 2 SPS06 Revision 60.00
• SAP HANA 2 SPS06 Revision 61.00
• SAP HANA 2 SPS06 Revision 62.00

 

What is the Business Impact?

Due to this programming error, an incorrect transaction status might be returned to the application level. In the worst case, this might lead to situations where SAP HANA has rolled back changes on the database level, which the application is not aware of. This can look from the application level as an inconsistency in business data while on the SAP HANA database level no inconsistency can be found by the technical consistency checks on the database level as described in SAP Note 1977584. This could lead to potential inconsistency or apparent data loss in business data due to incorrect transaction status.

 

 

What are SAP recommendations?

Update to SAP HANA 2 SPS06 Revision 63.00 or higher

Check SAP note 3213111 and 3198962 for more details

 

What actions SAP has taken to solve this issue? 

Standard templates are made available for you on Service Request App to request implementation of the above recommendation.

 

What action is recommended for you? 

Contact your SAP Enterprise Cloud Services Representative to discuss the details of the impacted systems, Target DB version compatibility with existing OS/application and plan the implementation of recommendations.

 

What will happen if recommendations are not applied?

SAP’s abilities for the provision of support may be limited and System Availability Service Levels may not apply. 

 

If you have any questions, please contact your SAP Enterprise Cloud Services representative. 

Thanks.

Rupesh Chavan

Server architecture for SAP HANA XS Advanced Runtime Platform

 SAP HANA extended application services, advanced model (XS advanced for short) provides a comprehensive platform for the development and execution of micro-service oriented applications, taking advantage of SAP HANA's in-memory architecture and parallel execution capabilities.

About SAP HANA XS Advanced

SAP HANA XS advanced offers a rich set of embedded services that enable end-to-end support for web-based applications including lightweight web servers, persistency services, and a configurable identity provider. Furthermore, the platform supports polyglot application development with a core set of pre-deployed runtimes that are accepted as industry standards, for example, node.js or JavaEE.

Although the built-in runtimes come with first-class development and monitoring support, the platform has an open architecture that allows you to add custom runtimes. This high flexibility makes it essential that you put a strong focus on security concepts, not only when configuring and setting up the infrastructure, but also throughout operating the system.

Architecture Overview

The basic system architecture has a classic 3-tier approach, we can see in below diagram 

There is a distinction between the overall SAP HANA system and the SAP HANA XS advanced application server. The SAP HANA system refers to the entire SAP HANA platform as part of the integrated solution. All services of the SAP HANA system share the same system identifiers (that is, instance number and SID) and are controlled by the hdbdaemon service.

The third tier, represented by an SAP HANA database, provides persistency services, that is, data storage. In contrast, the application server components in the middle tier are responsible for deploying, running, and monitoring the applications. Most security-related features such as authentication, authorization, and auditing are primarily enforced in this layer. End users interact on the client layer with system or business users that are authenticated by an identity provider (IdP), which is SAP HANA user management by default. However, both the server components and the applications themselves access the SAP HANA database only through technical database users that the platform generates implicitly. Direct access to the database is only intended for database administration and monitoring purposes.

The following diagram provides a more detailed overview of the technical system landscape of the XS advanced application server. All relevant components and storages used by the application server layer are highlighted with a gray background.

Technical System Landscape of XS Advanced Application Server

The XS advanced application server relies on the following SAP HANA services contributing to the integrated platform solution:

1. xscontroller (Controller, FileSystem Broker, Platform Router)
2. xsexecagent (Execution Agent)
3. xsuaaserver (UAA, UAA Broker and SAP HANA Service Broker)

Thanks 

Rupesh Chavan

HANA Administration Guide

Administration of Tenant Databases in SAP HANA System

 In SAP HANA systems, there are two types of administration tasks: those performed at the system level and those performed at the database level.

System Versus Database Administration

Tenant database systems have two levels of administration.

Some administration tasks are performed in the system database and apply globally to the system and all its databases. They include for example:

• Starting and stopping the whole system

• Monitoring the system

• Configuring parameters in configuration (*ini) files at system level

• Setting up and configuring tenant databases, for example:

• Creating and dropping tenant databases

• Disabling features on tenant databases

• Configuring system- and database-specific parameters in configuration (*ini) files

• Scaling out tenant databases by adding services

• Backing up tenant databases

• Recovering tenant databases

• Monitoring the database

• Provisioning database users

• Creating and deleting schemas, tables, and indexes in the database

• Backing up the database

• Configuring database-specific parameters in configuration (*ini) files

Some administration tasks are performed in the tenant database and apply only to that database. They include for example:

you can refer SAP HANA administration guide to get more detailed information about Tenant database administration. 

Thanks 

Rupesh Chavan

SAP HANA System Architecture #Hana

 An SAP HANA system includes multiple isolated databases and may consist of one host or several hosts.
An SAP HANA system is identified by a single system ID (SID) and contains one or more tenant databases and one System DB. System DB/Tenant databases are identified by a SID and a database name. We can identify differences between System DB and tenant database on the basis of tasks performed at the database level. We can connect respective databases from HANA Studio, SAP HANA Cockpit and DBACOCKPIT from an administration standpoint. 
The SAP HANA XS advanced application server is a layer on top of SAP HANA that provides the platform for running SAP HANA-based Web applications. It is an integral part of the SAP HANA system.
A HANA system may consist of one host or a cluster of multiple hosts. which is called a "multiple-host, distributed system, or scale-out system and supports scalability and availability" 

 Server Architecture 

An SAP HANA database consists of multiple servers/Services, for example, a name server, index server, preprocessor server, and so on. The most important Server is the index server. It contains the actual data stores and the engines for processing the data and runs in every tenant database.

Only the system database runs the name server. The name server contains landscape information about the system as a whole, including which tenant databases exist. It also provides index server functionality for the system database. The name server does not own information about the location of tables and table partitions in tenant databases. Database-related information is stored in the relevant tenant database catalogue.
Tenant databases require only their own index server. Servers that do not persist data, such as the compile server and the preprocessor server, run on the system database and serve all databases.

• ·        Set of database users

• ·        Database catalog

• ·        Repository

• ·        Persistence

• ·        Backups

• ·        Traces and logs

If the SAP HANA XS classic server is available, it runs embedded in the (master) index server of the tenant database by default.

Tenant Databases

SAP HANA supports multiple isolated databases in a single SAP HANA system. These are referred to as tenant databases.

A system always has exactly one system database, used for central system administration, and any number of tenant databases (including zero).

All the databases share the same installation of database system software, the same computing resources, and the same system administration. However, each database is self-contained and fully isolated with its own:

Although database objects such as schemas, tables, views, procedures, and so on are local to the database, cross-database SELECT queries are possible. This supports cross-application reporting. 

The System Database

The system database is created during either installation or conversion from a single-container system to a tenant database system. The system database contains information about the system as a whole, as well as all its tenant databases. It is used for central system administration.

A system has exactly one system database. It contains the data and users for system administration. System administration tools, such as the SAP HANA cockpit, can connect to this database. The system database stores overall system landscape information, including knowledge of the tenant databases that exist in the system. However, it doesn't own database-related topology information, that is, information about the location of tables and table partitions in databases. Database-related topology information is stored in the relevant tenant database catalog.

Administration tasks performed in the system database apply to the system as a whole and all of its databases (for example, system-level configuration settings), or can target specific tenant databases (for example, backup of a tenant database). For more information, see Administration of Tenant Databases.

Things to Remember About the System Database

• The system database does not have the same functionality as a tenant database.

• The system database is not a database with full SQL support.

• The system database cannot be distributed across multiple hosts, in other words, scale-out is not possible.

• If you need a full-featured SAP HANA database, you always have to create at least one tenant database.

• The system database does not support Application Function Libraries (AFL) and SAP liveCache applications.

• Cross-database access between the system database and a tenant database is not possible. The system database can show monitoring data from tenant databases (views in the schema SYS_DATABASES) but can never show actual content from tenant databases.

• The system database cannot be copied or moved to another host.

• SAP HANA options can only run in tenant databases.

• Tenant-specific configurations cannot be set in the system database. Only global settings are allowed.

• Features can only be restricted or disabled at a high level for tenant databases.

Thanks

Rupesh Chavan

 

 

How to start HANA Systems in SAP HANA Studio ?

Start a System

To initiate or start an SAP HANA system, we can utilize the SAP HANA studio. This will start all tenant databases except for those that were manually stopped.

Prerequisites

To continue with the process, it's important to have the login information for the operating system user, especially the <sid>adm user that was created during the HANA database installation. Please make sure you have this information before proceeding.

Procedure

1. In the Systems view, right-click the system you want to start and choose Configuration and Monitoring  Start System..

Note:  

Execute the start command from the system database. The Start System... command is not available from tenant databases. For more information about how to stop an individual tenant database, see Stop and Start a Tenant Database.

1. Enter the user name and password of the operating system administrator that was created when the system was installed (that is, <sid>adm user).

  3: The Administration editor opens in diagnosis mode and the database services start one by one. When all services have started, the system appears as operational () in the Systems view.

  4:  All tenant databases are started. However, if a tenant database was previously stopped individually, it is not started with the system. For more information about how to stop an individual tenant database, see Stop and Start a Tenant Database.

Thanks 

Rupesh Chavan

HANA Studio Guide