HANA Architecture Overview


SAP HANA Architecture Overview
The SAP HANA database is developed in C++ and runs on SUSE Linux Enterprise Server. SAP HANA database consists of multiple servers and the most important component is the Index Server. SAP HANA database consists of Index Server, Name Server, Statistics Server, Processor Server and XS Engine. 
Index Server
It is the prime server of SAP HANA that contains actual data and processing engines. This server processes the SQL and MDX statements when authentication and transactions are required.
Persistence Layer
This layer maintains atomicity and durability of transactions. It is accountable to make sure that the database is able to be restored to the recent state and transactions are properly executed or not left in the middle.
Preprocessor Server
This server analyzes text data and extracts information with the help of Preprocessors.
Name Server
 This server maintains the detailed information about the system topology. It keeps the updates about all the components and their location.
Statistic Server  
This server maintains log of other servers and their details such as status, performance, allocation/consumption of resources, etc. This data is used to keep track of the clients and alert monitors.
Session and Transaction Manager  
This server monitors the database transactions and their execution. When a transaction is committed or rolled back, Transaction manager informs the storage engines to take necessary measures.
XS Engine
This server facilitates communication between external applications and SAP HANA system via HTTP in a web browser.
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Different components of HANA:
SAP Host Agent:
According to the new approach from SAP, the SAP Host Agent should be installed on all machines that are related to the SAP landscape. It is used by Adaptive Computing Controller (ACC) to manage the system and Software Update Manager (SUM) for automatic updates.
SAP Host Agent have the following features:

Ø  SAP instance discovery and inventory

Ø  SAP instance control

Ø  Database monitoring and management

Ø  System or instance provisioning:

·        Hosting the infrastructure of SAP NetWeaver Landscape Virtualization Management (LVM), formerly known as SAP NetWeaver Adaptive Computing Controller (ACC)

·        Hosting software lifecycle (SL) tools interfaces

Ø  Operating system monitoring:

·        Using saposcol

·        Using Common Information Model (CIM) based infrastructures


Ø  IBM i-specific features:

·        Dynamically adopted authorization for SAP kernel 7.20 and higher

·        SAP ILE daemon (SAPILED)

·        SAP Database Performance Collector for IBM i

LM-structure:
LM structure of SAP HANA system contains statistics approximately current installation details. This information is used by software program update supervisor to install automatic updates on HANA system components.
SAP Solution Manager diagnostic agent:
This agent provides all the data to SAP Solution Manager (SAP SOLMAN) to monitor the SAP HANA system. After the SAP SOLMAN is integrated with the SAP HANA system, this agent provides information about the database at a glance, which includes the database state and general information about the system, such as alerts, CPU, or memory and disk usage.
SAP HANA Studio repository:
This helps the end users to update the SAP HANA studio to higher versions. The SAP HANA Studio repository is the code that does this process.
Software Update Manager for SAP HANA:
This helps in automatic updates of SAP HANA from the SAP Marketplace and patching the SAP host agent. It also allows distribution of the Studio repository to the end users.