SAP Basis Learnings

Basic troubleshooting process/steps follows as below. Database Starts: As on ABAP the first step is to check and start the database. No dedicated developer trace is created in the work directory as the database has its own logs. If the database does not start correctly, it should be visible within seconds and errors will be available within the DB logs. Developer traces: Refer to your DB logs. Startup: JSTART is called next, it takes the role of the Java instance controller which analyzes its configuration and initializes SAP signal handling and opens the control port. There is very rarely an issue with the initial load of JSTART. If for some reason this fails you most likely have a problem with your instance profile. Developer traces: dev_jstart Offline Deployment: The Java instance controller reads the instance definition and creates a child process that initializes JVM and starts the OFFLINE DEPLOYMENT program which performs the deployment steps in the Java database. In the ‘busine...

AS Java Cluster Architecture An AS Java cluster consists of several types of instances, each one of which has an instance number and can be started,  stopped and monitored separately. They are 1.          Central services instance The central services instance consists of a Message Service and Enqueue Service . They are responsible for lock  administration, message exchange and load balancing within the Java cluster. 2.         One or more Java instances A Java instance consists of an Internet Communication Manager (ICM) and one or several server processes . The ICM  handles requests coming from clients and dispatches them to the available server processes , which actually process the requests. 3.         Database The database stores system and application data. There is one central database. It is also possible to have several  application database...

  The architecture of SAP HANA has several components working together. The   main component of the entire SAP HANA architecture is the Index server   which stores and processes all the data. All the other components or engines such as Name server Relational database engine OLAP engine, etc., are linked to the index server and work with it. We will learn about all the architectural components and services in detail in this tutorial. When a user is working on SAP HANA, it is interacting with the client application. A session between the client application and the data source (which is SAP HANA in-memory database) is established which connects the two. The Session and Transaction Manager handle the session initiation and management. Once, the client is connected with the database, queries and data are launched in languages such as  SQL  and SQLScript.  SQLScript is the scripting language of SAP HANA Database . SAP HANA also supports applications and prog...